1040 IEEE JOURNAL ON SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 6, NO. 6, NOVEMBER/DECEMBER 2000

III–V Semiconductor Heterojunction Devices Grownby Metalorganic Chemical Vapor Deposition

Russell D. Dupuis, Fellow, IEEE

Invited Paper

Abstract—Several important early developments in the metalor-ganic chemical vapor deposition technology relate to the demon-stration of high-performance AlGaAs–GaAs injection lasers andsolar cells in the late 1970s. It has been nearly 24 years since thefirst semiconductor injection lasers grown by metalorganic chem-ical vapor deposition (MOCVD) were made and nearly 22 yearssince the first continuous-wave quantum-well injection lasers weremade by this process. In this past 20-odd years, MOCVD has beendeveloped for the production of AlGaAs, InAlGaP, InGaAsP, In-AlGaN, and a variety of other compound semiconductor materials.It is now the dominant technology for the production of light-emit-ting diodes, injection lasers, solar cells, photodetectors, and het-erojunction bipolar transistors and a variety of other solid-statedevices. This paper will review some of the early developments inthis technology.

Index Terms—Aluminum gallium arsenide, heterojunctionlasers, metalorganic chemical vapor deposition, quantum-welllasers.

I. INTRODUCTION

T HE METALORGANIC chemical vapor deposition(MOCVD) technology for the growth of III–V compound

semiconductors developed quickly over the past twenty yearsto become the dominant epitaxial materials technology forboth research and production. Because of the improvementin the material quality produced by MOCVD, many impor-tant III–V devices have become commercially viable. TheMOCVD epitaxial growth technology was first reported inthe scientific literature in 1968 by Manasevit [1],1 althoughsimilar processes and experimental results were previouslydescribed in the patent literature by other workers, e.g., Scottet al. [2], Miedereret al. [3], and Ruehrwein [4]–[6], prior to1967. Manasevit was primarily interested technologies for theheteroepitaxial growth of III–Vs on insulating substrates, theanalog of the silicon-on-insulator (SOI) and silicon-on-sapphire

Manuscript received July 17, 2000. The work described here that wasperformed by the author at Rockwell International was partially sponsored byRockwell’s Internal Research and Development funding and by the EnergyResearch and Development Administration (ERDA) (which later became partof the Department of Energy). AT&T Bell Laboratories sponsored the workperformed at Bell Labs.

The author is with The University of Texas at Austin, Microelectronics Re-search Center, Austin, TX 78758 USA (e-mail: dupuis@mail.utexas.edu).

Publisher Item Identifier S 1077-260X(00)11610-7.

1In order to protect the North American Rockwell patent position, no detailson the growth process are described in this paper.

(SOS) technology that he had developed earlier [7]. In fact,this first paper on MOCVD concerned the epitaxial growth ofGaAs on insulators and the actual epitaxial process isnot evenmentioned[1]! While he and other workers studied the growthof III–Vs by this process in the early and middle 1970s, theywere unable to demonstrate materials quality comparable tothat of other III–V epitaxial technologies such as liquid-phaseepitaxy (LPE) and halogen- and hydride-based vapor-phaseepitaxy (VPE) [8]–[11].

In 1977, Dupuiset al. reported the first AlGaAs–GaAshigh-efficiency solar cells grown by MOCVD—these were thefirst “device-quality” heterojunctions grown by MOCVD [7].A short time later, Dupuiset al. reported room-temperature op-eration of high-quality AlGaAs–GaAs double-heterostructure(DH) lasers with pulsed threshold current densities as low asthose demonstrated for similar devices grown by liquid-phaseepitaxy (LPE) [13], [14]. This announcement was followedby results showing CW operation of by the end of 1977 [15]and the operation of lasers with AlGaAs active regions in thatsame year [16]. These results firmly established the potentialof the MOCVD process to produce high-quality Al-bearinglayers from vapor-phase sources. This paper will review theearly advancements in MOCVD technology and speculate onthe future applications of this technology.

Over the years since 1968, there have been several othernames applied to this process, including: metal alkyl vaporphase epitaxy (MAVPE), metalorganic VPE (MOVPE),organometallic CVD (OMCVD), and organometallic VPE(OMVPE). However, Manasevit first used the term “metalor-ganic” because that was the common term applied to the “metalalkyl” compounds at this time and “CVD” because he feltthat the process could be broadly applied to “chemical vapordeposition” of many different materials, including polycrys-talline and amorphous films—the term “vapor-phase epitaxy”is a special case of the more general term “CVD.” Later, theterm “organometallic” came to be applied to these specificcompounds by the synthetic chemists studying these materials.

II. EARLY MOCVD GROWTH OF COMPOUND

SEMICONDUCTORS

The growth of compound semiconductors using ColumnIII metalorganic compounds and Column V hydrides beginsin 1960 with the work of Didchenkoet al. who explored the

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reactions of trimethylindium [In(CH) , TMIn] and phosphine(PH ) at 300 C [17]. While these authors claimed thatthe adduct formed by this reaction “decomposes sometimesexplosively into InP and CH,” they did not establish conclu-sively that the “dark gray powder” formed was in fact InP. In1962, Harrison and Tompkins published a paper describingexperiments in which they combined 1 : 1 mixtures of arsine(AsH ) and trimethylgallium [Ga(CH) , TMGa] then heatedthe reaction products to 200 C to form a “red” compoundthat they claimed was GaAs [18]. Another early considerationconcerning the growth of III–V semiconductors by MOCVDwas made by Dr. R. A. Ruehrwein of Monsanto who applied forpatents in 1961 on many of the VPE processes for the growthof III–Vs, including the idea of using metalorganic Column IIIprecursors in combination with Column V hydrides [4]–[6].2

In late December 1967, Manasevit submitted his firstpaper describing epitaxial growth of GaAs on insulating sub-strates—however, the actual growth process was not mentioned[1]. This work was presumably performed without knowledgeof the previous related patents and prior published resultsdescribing the “bulk” growth of semiconductors using metalor-ganic compounds.3 Manasevit did not describe the MOCVDgrowth process because he wanted to patent this invention—infact, shortly after Manasevit’s first paper appeared, Rockwellfiled a patent application on MOCVD, Ser. no. 705 213, on Feb.13, 1968. However, this was denied because of the previousRuehrwein patents [4]–[6]. The first detailed description of theMOCVD process was given in a later paper [19]. Somewhatironically, Rockwell applied again for a patent on MOCVDin 1978 anticipating that the Monsanto patents were going toexpire—they were granted a patent in 1983. This delay wasfortunate for Rockwell because this patent covers the timeperiod when MOCVD actually was making products with verylarge profits [20]!4 In 1997, the Rockwell patent was ruledinvalid by a United States Federal Court [21]. Subsequently, itwas reinstated upon appeal by Rockwell.

It is interesting to note that, along with MOCVD, many im-portant innovations in III–V epitaxial growth technologies werefirst explored in the 1966–1967 time frame. For example, “opentube” hydride VPE growth of III–Vs was first reported by Ti-etjen and Amick in 1966 [22]. Liquid-phase epitaxial growth ofAlGaAs was first reported in 1967 by Rupprechtet al. [23] andArthur reported his first studies of the properties of Ga and Asmolecular beams in 1967 [24], which ultimately led to molec-ular beam epitaxial growth of GaAs by Cho in 1970.

The first report in a scientific journal regarding devicesfabricated from MOCVD-grown material was a 1969 paper byWaldner and Rouse, who fabricated GaAs FETs from materialgrown by Manasevit [25]. Over the next few years, Manasevitand co-workers explored the growth of III–V, II–VI, andIV–VI compounds by MOCVD [26]–[28]. Manasevit’s workconcentrated on the growth of thin semiconductor films onvariousinsulating oxide substratesincluding sapphire, spinel,

2These patents prevented Rockwell from patenting the MOCVD process in1968.

3However, Tompkins’ paper is referenced in Manasevit’s first paperdescribing MOCVD [19].

4This patent was still the subject of litigation as of July 2000.

beryllium oxides, etc. The reason for this focus was his interestin III–Vs on insulators—the analog of the Si-on-sapphiretechnology he pioneered earlier.5 Much of Manasevit’s workwas “proof-of-concept” growth studies on insulators and thepurity of the alkyl sources was still very far behind that of otherprecursors used for III–V epitaxial growth. Furthermore, theMOCVD process is very sensitive to oxygen (more so thanLPE and VPE), and the quality of the films is degraded whensmall oxygen leakss exist in the reactor system. Given the stateof the art in reactor system design and construction in the early1970s, this oxygen sensitivity created serious problems, espe-cially for the growth of Al-containing alloys. These combinedeffects led to low carrier mobilities, high background impurityconcentrations, poor surface morphologies, and generally lowphotoluminescence efficiencies compared to those achieved byother III–V materials technologies.

By the time Manasevit’s first paper appeared in 1968, manyprocesses for the growth of III–V epitaxial films were underactive study and development. Holonyak was the first to in-vestigate the epitaxial growth of III–V compound semiconduc-tors [29]. He used a closed ampoule process to grow GaAs,GaAsP, and GaP on a variety of substrates, also creating thefirst III–V heterojunctions. Since the early 1960s and into themiddle and late 1970s, other III–V materials technologies dom-inated the research and production efforts worldwide, including:1) vapor-phase epitaxy (VPE) using Column V halides (e.g.,AsCl ) and Column III metals [30];6 2) VPE using ColumnV hydride sources (e.g., AsH) and Column III trichlorides,e.g., GaCl [31];7 3) liquid-phase epitaxy (LPE) using ColumnIII metal solutions (e.g., Ga melts with GaAs source material)[32];8 4) molecular-beam epitaxy (MBE) using pure elementalsources (e.g., Ga and As) [33]. Already in 1968, when Mana-sevit’s paper first appeared, the VPE and LPE technologies wereproven for the growth of a variety of “high-performance” III–Vdevices. By 1973, hydride VPE dominated the production ofGaAsP light-emitting diodes (LEDs) and halide VPE dominatedthe production of high-purity GaAs for electronic devices. LPEwas the dominant technology for many III–V compounds, es-pecially Al-containing devices, including AlGaAs LEDs, lasers,solar cells, and other heterojunction devices. By 1975, MBE wasbeing actively researched by a few groups, particularly at BellLabs [34] and IBM [35]. Consequently, there was not much in-terest in MOCVD—it was viewed as just “another” III–V mate-rials technology—and the materials results seemed to be muchworse than that achieved by the other III–V epitaxial growthtechnologies.

5At this time, semi-insulating GaAs was prepared by doping the ingot withdeep centers, e.g., Cr, to provide deep electron traps to make the material “in-sulating.” This process was “unreliable” in that the insulating behavior was notuniform within an ingot and also would change after thermal cycling.

6N. Holonyak, Jr., working at General Electric, initiated the “closed-tube”VPE process using iodine and chloride transport for the growth of III–Vs in1960. Subsequently, others (R. A. Ruehrwien and F. V. Williams at Monsanto)expanded this into an open-tube process using chloride transport. This becamethe dominant form of halide VPE. See the paper “From Transistors to LightEmitters,” by N. Holonyak, Jr. in this issue.

7An early summary of hydride VPE appears in [31].8LPE growth of III–Vs was first described by R. Nelson (RCA Laboratories)

in 1961 at the Solid State Device Conference (Stanford, CA). This work waspublished in [32].

1042 IEEE JOURNAL ON SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 6, NO. 6, NOVEMBER/DECEMBER 2000

In 1975, Seki and co-workers described the first“high-quality” GaAs films grown by MOCVD [36].9 Thesewere “homoepitaxial” films on GaAs substrates grown usingspecially purified triethylgallium [Ga(CH ) , TEGa] andAsH . The electronic properties of these films were studiedas a function of temperature and 300 K mobility values of

– cm /V s and a maximum mobilityvalue of cm /V s forcm was measured at 77 K. These values were the highestreported to that date for MOCVD-grown GaAs and comparedfavorably to the values then obtained for “high-purity” GaAsgrown by the more “conventional” AsCl–Ga–H system. Thiswas a remarkable result at the time and showed that if carefulpurification routes were used for the sources, the fundamentalelectronic properties of GaAs grown by MOCVD could begood enough for the demonstration of usefulelectronicdevices.

III. D EVELOPMENT OFMOCVD FORINJECTIONLASERS

While these results clearly established the fundamentallysound MOCVD capabilities for the growth of “device-quality”GaAs for “electronic devices,” the growth of high-qualityAl-containing films was still problematical This was an impor-tant issue that I began to study in 1975. In March 1975, I joinedthe Rockwell International Electronics Research Center (laterpart of the Electronics Operations) in Anaheim, CA, to studythe electrical and optical properties of MOCVD-grown III–Vmaterials. I started work by setting up a photoluminescencesystem for III–V materials characterization. For this purpose,I ordered a new Ar-ion laser, photomultiplier, picoammeter,etc. While waiting for this equipment to arrive, I spent a fewweeks studying the electrical properties of GaAs/sapphireheteroepitaxial films grown by Manasevit and Simpson.10

I had previous experience with the solution growth of InGaPand the LPE growth of GaAs, AlGaAs, and AlGaAsP at UIUC.In addition, I had studied the LPE growth of N and Zn-O dopedGaP LEDs at Texas Instruments. Furthermore, I also had someindirect knowledge of the VPE growth of GaAsP alloys fromexperiences gained during my Ph.D studies at UIUC, where Iworked with VPE crystals grown at Monsanto. I realized thatthe MOCVD process could do something very unique—it couldprovide aVAPOR PHASEsource of Al! While I knew that theconventional forms of VPE could handle Ga, In, As, P, Sb, and Nvery well, the VPE processes could not easily be used to trans-port Al due to the reactivity of the pure element and its sub-chlorides [37].11 LPE could handle Al but was limited by the“tyranny of the liquid-solid phase diagram,” generally poor re-producibility, uniformity, and surface morphology, and, I knew,was very limited in the epitaxial wafer area that could be pro-duced in one run. However, MOCVD was a process that ap-

9This work employed a specially purified TEGa source produced by Sum-itomo Chemical Co., Ltd. Japan.

10William I. (Bill) Simpson was Manasevit’s technician and was responsiblefor reactor construction and maintenance, operation of the system, and materialscharacterization.

11Al chlorides attack quartz at temperatures typically used for VPE growth,forming alumina, consequently the VPE growth of Al-containing III–Vs wasalways compromised by oxygen and Si impurities as well as the catastrophicfailure of the reactor tube.

peared to be scalable (like VPE) and able to grow a wide va-riety of III–Vs—in fact, virtually all of them—with the specialand important bonus of being able to provide Al to the surfaceduring the growth of an epitaxial film (like LPE). This importantcapability intrigued me and was a prime reason why I decided towork on MOCVD growth as well as on characterization and de-vice fabrication. This would produce a direct method to providethe quick “feedback” necessary to improve the materials qualitynecessary to make AlGaAs–GaAs heterojunction devices.

In order to have control of the materials I would be char-acterizing, I decided to build a reactor system myself to studyMOCVD growth of device structures and heteroepitaxial andhomoepitaxial III–V films. I was very familiar with this “growand characterize” mode of materials and device research, sinceduring my M.S. and Ph.D. research in N. Holonyak, Jr.’s, lab atthe University of Illinois in Urbana-Champaign, we built muchof our own growth apparatus, even to the point of wiring ourown furnace elements.12 Consequently, I already had some ex-perience in building crystal growth systems in Holonyak’s lab.In addition, after leaving the U of I, I worked in the Optoelec-tronics Group of the Semiconductor Division of Texas Instru-ments, Inc., Dallas, TX. There I built a new large-scale LPEsystem capable of growth on three 2.0 in diameter wafersfor thegrowth of GaP : N green and GaP : Zn–O red LEDs, providingme some additional “industrial” experience in the design andfabrication of semiconductor epitaxial growth systems.

I modeled my first Rockwell MOCVD system on the existingdesign of Manasevit’s MOCVD reactor that Simpson had built,taking particular care in the reduction of “dead space” and theleak integrity of the gas panel. Almost all of the gas valves,Swagelok fittings, and “Rotameter;” type gas flow meters, aswell as the rf generator, hydrogen purifier, vacuum pumps, andother components that I had to work with were “used.” However,I took special care with the cleanliness and the assembly of thecomponents to ensure that the system was as clean and leak-tightas possible.13 I knew that this would be critically important inthe handling and use of Al-conaining alkyl compounds. Thissystem had a vertical quartz chamber with a rotating (at10–20rpm) horizontal SiC-coated graphite susceptor2.0 in in di-ameter and rf heating. It operated at atmospheric pressure andemployed a specially designed “vent-run” gas manifold, whichpermitted the metalorganic source flows to be directed into avent line or into the reactor, making the gas switching time veryshort. A photograph of me working with this system taken in Oc-tober 1975 is shown in Fig. 1. A close-up of the reactor chamberand rf-heated susceptor is shown in Fig. 2. At this time, I onlyhad TMGa and AsHsources mounted on the system. Later in1975, I added trimethylaluminum [Al(CH) , TMAl] and thedoping sources HSe and diethylzinc [Zn(CH ) , DEZn)] sothat I could grow n-type and p-type doped films and AlGaAsheterojunction devices. I grew a variety of p- and n-type epi-

12In Prof. N. Holonyak Jr.’s lab at the U of I, we had hand-made heatingelements for over 30 individual furnaces for the growth of InGaP crystals by asolution-growth technique and also an LPE system for growing AlGaAs–GaAslaser structures.

13All of the 316 stainless steel tubing was solvent cleaned and passivated andetched with HF : HNO : H O and carefully dried using methanol. Furthermore,all valves were solvent cleaned ultrasonically and all of the Swagelok ferruleswere Au-plated to prevent them from galling when assembled.

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Fig. 1. Photograph of me with the first MOCVD reactor I built at RockwellInternational in 1975. Photograph taken October 20, 1975.

Fig. 2. Photograph of the MOCVD reactor chamber with a large-area (0001)sapphire substrate loaded on the 2.0-in diameter. SiC-coated graphite susceptor.Photograph taken October 20, 1975.

taxial layers on GaAs : Cr semi-insulating substrates to deter-mine the doping concentration versus dopant molar flows forGaAs and AlGaAs films using Hall-effect characterization. Thework on the optimization of the growth rate, V/III ratio, growth

temperature, metal alkyl molar flow rates, and dopant flows,etc., took several months and was complicated by the fact that Iinitially had to rely primarily upon 300 K and 77 K Hall-effectdata and surface morphology examination by Nomarski opticalmicroscopy since my PL system was not operational in the earlyphases of this work. However, by working out the growth con-ditions for the best morphology and mobilities, the PL was alsopretty good as far as I could tell. I found that the III/V ratio andgrowth temperature were critically important parameters for thegrowth of the best AlGaAs. Since I had no “PL standards” to ex-amine for comparison, all of this work was performed on a “rel-ative” basis. Rockwell had a Physical Electronics PHI Augerelectron spectroscopy system in a nearby building so I took afew samples over there to study the AlGaAs–GaAs interfaceabruptness and the oxygen impurity concentrations in the Al-GaAs films.

By early 1976, I had moved on to growing heterojunctiondevices—I was particularly interested in semiconductor lasers,which I knew about from my graduate student days at theU of I. The first device structure I grew was a simple GaAsp–n junction. After I processed the devices from the wafer, Idiscovered that the current versus voltage (– ) character-istics looked good on the curve tracer—and the device–responded to the microscope light—so I decided to growa “solar cell” structure using a thin AlGaAs window layeron top. After working out the growth conditions for variousAl Ga As alloy compositions, I found the conditions for awide-bandgap alloy with Al composition like thatused for similar LPE-grown solar cells. After I processed thiswafer into simple “solar cell” devices, I took them outside thebuilding to “test” the devices. Using a digital multimeter, Ifound a large photocurrent was generated under such “one-sun”“Air Mass one or so” illumination conditions.14 In additionto being the first MOCVD-grown device of its kind (to myknowledge), this result was interesting because the US Gov-ernment was starting to fund “alternative energy” researchunder the auspices of the Energy Research and DevelopmentAdministration (ERDA). Further, optimization of the growthand more detailed device testing led to my publication of thefirst paper on the MOCVD growth of solar cells [12]. Theseuncoated devices exhibited 1-sun Air Mass Zero (AM0—solarflux conditions in space) short-circuit current densities of 24.5mA/cm , open-circuit voltages of 0.955 V, fill factors of

0.70 and power conversion efficiencies as high as 12.8%which compared well with the record efficiencies reported forLPE-grown devices of 17.2% for antireflection-coated cells.15

Subsequently, my Group at Rockwell received a contract fromERDA for solar-cell research, including the MOCVD growthof GaAs solar cells on “low-cost” substrates, e.g., glass, Mo,and Mo/glass composites [38]. I began the AlGaAs–GaAs solar

14The term “Air Mass Zero” denotes photon flux conditions identical to outerspace in the near earth region due to illumination from the Sun. “Air Mass One”corresponds to the solar flux conditions at the surface of the earth at sea level ona clear, cloudless day when the Sun is at its zenith. “Air Mass Two” correspondsto a reduced solar flux corresponding to a hazy day.

15These values are uncorrected for contact area and reflections from the Al-GaAs surface. I estimated that anti-reflection coatings would raise the efficiencyby about 30–35% to make the AM0 efficiency of these MOCVD cells as highas 17.28%.

1044 IEEE JOURNAL ON SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 6, NO. 6, NOVEMBER/DECEMBER 2000

cell research at Rockwell-Anaheim in this program using thisfirst MOCVD reactor. The MOCVD technology is now thedominant materials growth technique for all III–V solar cells.

In 1975 and 1976, a few groups reported the character-istics of MOCVD-grown GaAs films and AlGaAs–GaAsheterostructures. For example, Andre and co-workers reportedon the growth of p-type GaAs and AlGaAs films on GaAssubstrates for photocathodes [39]. The electron diffusionlengths in various p-type GaAs layers were measured to becomparable to that of LPE-grown films. However, many defectswere observed in the AlGaAs films and no electrical or opticalproperties of the AlGaAs films were given. In 1975, SidneyBass reported that the highest 300 K electron mobility forhis MOCVD-grown n-type GaAs was cm /V s[40]. Also, in 1976, Allenson and Bass reported the growthof GaAs photocathodes on GaAs substrates by MOCVD [41].Undoped layers were p-type with cm and

cm /V s. Intentionally doped p-type films withcm cm were obtained using

DEZn as a dopant. No data on AlGaAs were presented. Theelectron diffusion length was comparable to LPE-grown filmswith similar hole concentrations. Also, in 1976, Whiteet al.published a comparative study of deep traps in “bulk” GaAsand LPE-, chloride VPE-, and MOCVD-grown epitaxial GaAsfilms [42]. This work showed that the MOCVD-grown filmshad a larger variety of electron traps than the other materialsalthough the absolute trap concentrations were not measured.

My work in 1976 focused on MOCVD growth of Al-GaAs–GaAs solar cells and the study of doping in AlGaAs.In addition, the new funding provided by the ERDA solar-cellcontract allowed me to construct a second MOCVD reactor withmany new components, including new stainless-steel NuproModel 4H bellows-sealed valves, Tylan; Model 260 electronicmass flow controllers, and special Hoke three-port, low-deadvolume bellows-sealed switching valves with face-sealingfittings using metal gaskets. Furthermore, I designed and builtan improved reactor control system using a 16-channel Tylanelectronic sequencer. Finally, I designed and built a gas distri-bution system with the TMGa, TMAl, and DEZn metalorganicsource “bubblers” attached to the low-volume valves to providefor rapid switching. The electronic sequencer contained anoptical card reader and could be programmed with punched“IBM cards” to load a “run recipe” containing many “steps”into memory for later execution. Again, I was very concernedabout the effects of oxygen on the growth of the AlGaAs films,and although most of the stainless-steel tube fittings wereSwagelok, I used careful cleaning, assembly, and sealing tech-niques to realize the best possible leak integrity of the system.16

I also designed and built special all-welded 316 stainless steelmetalorganic source cylinders using electron-beam welding sothat the alkyls would stay as pure as possible while they wereused. I transferred commercially supplied alkyls into thesevessels using a vacuum transfer procedure. To my knowledge,these are the first high-purity all-welded metalorganic source

16I did not have access to a conventional He mass-spectrometer leak detector,however (we did not have enough money to buy one), so I employed a “rate ofpressure rise” test using a Hg diffusion pump and a thermocouple vacuum gaugeto evaluate the system integrity.

Fig. 3. Photograph of the second MOCVD reactor I built at Rockwell in1976. This system is “computer controlled” and contains a more advancedlow-dead-volume gas-switching manifold. Photograph taken January 10, 1977.

cylinders ever made. A photograph of my “more advanced”second MOCVD reactor is shown in Fig. 3. At this time, therewas no commercial vendor of MOCVD reactors so everyonehad a different type of system because they were all built byindividual researchers—every reactor was unique. I believethat, at the time this second reactor was completed (late 1976),this was the most advanced reactor being used for MOCVDgrowth.

By the end of 1976, this reactor was fully operational and Istarted to work on AlGaAs–GaAs solar cells to compare withthose created with my other “first” reactor. Don Yingling17 wasthe primary operator of that “first” system, while I was the soleuser of the “new” system. From the 300K PL that I measuredusing AlGaAs–GaAs–AlGaAs double-heterostructure (DH)“standard samples,” it was clear that this new MOCVD systemwas performing better. The uniformity of the depositionwas readily optimized using AlGaAs films withgrown on sapphire substrates. The optical interference ofthese wide-bandgap films with the underlying AlO substratemade it easy to determine how uniform they were. A colorphotograph of a highly uniform AlGaAs film grownon a 1.5-in diameter AlO substrate is shown in Fig. 4.18 Inthe study of AlGaAs for solar cells, I grew films with Al alloycompositions from to . I grew my first pureAlAs films accidentally when the TMGa source ran out duringan AlGaAs run.

17Don Yingling was a technician working on LPE growth of GaP LEDs whenhe and I met at Texas Instruments in Dallas, TX in 1973. I hired him in 1976 tocome to Rockwell to work on the solar-cell program and he operated the “first”MOCVD reactor while I built and operated the “second” one. Later, he moved toXerox Palo Alto Research Center to build and operate an MOCVD reactor and towork on lasers with Dr. Robert D. Burnham and Dr. Donald R. Scifres. A lot ofthe features of my second reactor were used in the Xerox system. Subsequentlythe Xerox MOCVD reactor was used to grow laser material for the “start-up”of Spectra Diode Laboratories (now SDL Inc.).

18The AlGaAs alloy compositions were determined by a combination of300K PL (for direct bandgap alloys), absorption measurements (for indirectalloys), and X-ray rocking curves for films grown on GaAs substrates.

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However, the AlAs films rapidly degraded when exposedto air so I did not pursue this composition futher. However,Al Ga As films with were very stable and I usedthis alloy composition in some of the solar cell structures thatI grew.

I was also interested in trying to demonstrate an injectionlaser using the MOCVD process so I started to work on lasersgrown in this reactor. Since I had made many injection lasersduring my Ph.D. research in N. Holonyak, Jr.’s, lab at the Uni-versity of Illinois, I had a great deal of experience with lapping,metallizing, cleaving, and testing such devices. After growingthe wafers, I processed them into laser bars for electricaland optical testing. I was successful in demonstrating 300 Kpulsed laser operation with low threshold current densities

kA/cm in early May 1977 and quickly wrote apaper describing these results [14]. The first lasers had fourcleaved edges and consequently, some of them operated insome “total internal reflection” mode. Subsequently, I preparedconventional Fabry–Perot devices using sawed or scribed sidesand cleaved facets. I tested some of the diodes using a simple“pressure clip” mounting and others I used a more normal“p-side down” bonding scheme using In solder to the p-sideand thermo-compression wire bonds to the n-type side.

I also submitted a “Late News Paper” with these first laserresults to the 1977 IEEE Solid State Device Research Confer-ence which was held at Cornell University, Ithaca, NY, at theend of June 1977. The Late News Papers were considered onthe Sunday before the meeting began. Late Sunday evening,I learned from N. Holonyak that this paper was accepted. R.Dixon (Bell Labs, Murray Hill, NJ) was on the Program Com-mittee and he told me that the paper was accepted with the con-dition that I “tell all about how the results were achieved.” I gavemy Late Paper in a very full conference room and there werelots of questions about the details of how this work was per-formed. I could tell there was lots of excitement but there werealso lots of skeptics as well. Many of the skeptics were finallyconvinced later in April 1978 when my paper on the CW oper-ation of MOCVD-grown AlGaAs–GaAs lasers was published[15].

These first MOCVD lasers employed a conventional Al-GaAs–GaAs DH structure. Since the best reliability for LPElasers reported at that time was being achieved with AlGaAs“active regions,” after the DRC, I decided to try this typeof structure. Furthermore, there were questions regardingthe quality of the AlGaAs produced by MOCVD. In earlyAugust 1977, I succeeded in operating pulsed AlGaAs DHlasers with AlGaAs –0.12 active regions operatingat –829 nm, i.e., at significantly shorter wavelengthsthan the nm laser emission of the GaAs active regiondevices I reported earlier [43]. These results were the first tounequivocally establish that MOCVD-grown AlGaAs was ofdevice quality.

At the 1977 DRC, my Ph.D. dissertation advisor, Prof. N.Holonyak, Jr., presented another very important laser result. Hedescribed the operation at 77 K of LPE-grown injection lasershaving a “quantum-well” active region—this active region wascomposed of ultrathin ( nm) InGaAsP layers.19 These

19These results are published in [44].

Fig. 4. Uniform AlGaAsx � 0:80 film grown on 1.5-in diameter sapphiresubstrate grown in the second reactor. The blue and pink colors are due tothe optical interference between the film and the sapphire. Photograph takenFebruary 23, 1977.

are the firstnon-AlGaAs-based“quantum-well” lasers to op-erate and the first quantum-well lasers not grown by MBE—infact they were also the first QWdiode lasers. After I gave mypaper at the DRC, Holonyak suggested the possibility of thegrowth of ultrathin AlGaAs–GaAs heterostructures using myMOCVD reactor. When I described the reactor control and gasswitching systems I had built just for the purpose of controllingthe growth of abrupt heterointerfaces, he was very surprised thatI had such an elaborate system already prepared with the exactcapabilities needed to grow such ultrathin layer structures. Weimmediately began making plans for collaboration on the use ofmy MOCVD reactor for the growth of AlGaAs–GaAs injectionlasers using quantum-well heterostructures (QWHs). This ledto the study of the interface abruptness of MOCVD-grown Al-GaAs–GaAs heterojunctions, showing that the interfaces wereabrupt to the limits of Auger electron spectroscopy measure-ments [45], [46].

Other workers had reported difficulties in the MOCVDgrowth of AlGaAs. For example, Blakeslee and Bischoff[47] reported in 1971 that no PL was observed from AlGaAs( ) grown by MOCVD on GaAs substrates whileLee et al.reported that the PL spectra for AlGaAs films with

showed an intense m “deep-level”emission [48]. In fact, later in 1978, Stringfellow and Hall hadreported that AlGaAs ( ) alloys grown byconventional MOCVD were highly compensated and exhibitedno PL emission [49]. In 1978, Hallaiset al. reported that theinterface width of AlGaAs–GaAs ( ) heterojunc-tions was 30–65 nm and that such AlGaAs layers were highlyresistive if grown at temperatures less than800 C [50].These reports clearly showed that growing high-quality abrupt

1046 IEEE JOURNAL ON SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 6, NO. 6, NOVEMBER/DECEMBER 2000

AlGaAs–GaAs heterojunctions by MOCVD needed to be donewith care.

After my laser results were published in late 1977, otherworkers began to have some success in growing AlGaAs.For example, Nelsonet al. reported the successful growth ofAlGaAs–GaAs solar cells in December 1977 with the cellsshowing concentrator AM2. 1 (at 933-sun concentration mea-sured outside in Palo Alto, CA) short-circuit currents of 20.9mA/cm and open-circuit voltages of 1.01 V forAR-coatedcells. No data on 1-sun AM2 efficiencies were given, however,and no AM0 data were reported so it is hard to know how thesedevices compare to my first MOCVD cells[51].

In 1977 and 1978, I grew many AlGaAs–GaAs QWH wafersthat I sent to Holonyak for photopumping, leading tothefirst demonstration of photopumped CW quantum-well laseroperation at 300 K[52]. Later, we succeeded ininjection laseroperation of single-QW and multiple-QW structures[53],[54]. This work led to our report of the very first CW 300 K“quantum-well lasers,” a term that we invented to describethese devices [55]. This opened up many new avenues of work,including the study of graded AlGaAs cladding regions to form“graded-index” (GRIN) laser structures. Also, we collaboratedon a variety of experiments related to the study of phononcoupling to QW laser emission [56].

I was also interested in forming “index-guided” stripe-ge-ometry lasers using nonplanar growth. Since I was familiarwith the “kinetically limited” nonplanar etching of GaAsusing NH OH–H O solutions, I used this etch to produce“nonplanar” substrates to grow AlGaAs–GaAs lasers [57].These “channel-guide” lasers were grown on etched channels

5–8 m wide and 250–350 nm deep. The AlGaAs–GaAsSQW laser structures were grown in these channels, creatinga nonplanar QW active region that had higher optical lossesfor the higher-order “transverse-parallel” lateral optical modes,resulting in “single mode” laser operation at 300 K. Later,other workers used this approach of growing on nonplanar“V-groove-etched” substrates to produce “quantum wires,”i.e., structures with a “one-dimensional” confinement ofelectron–hole pairs.

Another novel type of laser that I studied is an AlGaAs–GaAsinjection laser device using distributed Bragg reflectors (DBRs)as cladding layers [58]. This structure employed n- and p-type“dielectric stack” cladding layers composed of twelve to four-teen pairs of alternating layers of doped AlGaAs andGaAs on each side of an undoped GaAs active region. The ab-sorption edge of the GaAs layers in the “mirrors” is “Burstein-shifted” to higher energy due to the high doping concentrationsemployed in these regions. The DBR period was

nm for various wafers. I designed these mirrors using asimple Bragg reflector model and an HP Model 6825A DesktopComputer. These lasers operated in a pulsed mode at 300 K with

kA/cm . I believe these were the first epitaxial DBRsever grown. Later, such epitaxial DBR mirrors would becomeinstrumental in the operation of vertical-cavity surface-emittinglasers (VCSELs).

The reliability of MOCVD-grown AlGaAs–GaAs lasers wasan issue that was frequently brought up at conferences and indiscussions that I had with many researchers, including Ralph

Fig. 5. Large-area MOCVD-grown AlGaAs–GaAs QW laser wafer.

Fig. 6. Spectra (300 K) for the first MOCVD-grown AlGaAs–GaAs CWinjection laser.

Logan, Franz-Karl Reinhart, and others from Bell Labs. Once,in a particularly heated question-and-answer session after oneof my talks, B. Hakki (from the Laser Development Group atBell Labs) asked when I was going to have reliability data—Itold him whenever someone would pay me to do the measure-ments [59]! Later, when I was at Bell Labs, I would work withothers (Bob Hartman, Frank Nash, and Lou Koszi) to determinethe useful lifetime of AlGaAs QW lasers grown by MOCVD[60]. However, at Rockwell, I had very limited resources to dothis type of testing—I only had one stable precision currentsupply to run CW diodes, no diode temperature controllers,no automatic optical output power controllers, and no facetcoatings, no diamond heat-sinks or other CW device bondingtechnology. So one weekend, I set up an MOCVD-grown

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Fig. 7. Auger-electron spectroscopy profiling analysis of MOCVD-grown AlGaAs–GaAs multiple-quantum-well heterostructure showing abrupt interfaces.

AlGaAs–GaAs MQW laser diode (the active region had sixGaAs QWs and five Al Ga As barriers) to test under“constant-current” conditions at whatever junction temperaturewould arise during testing. I went into the testing lab severaltimes during the day and the evenings to check on the “diodelifetime.” As the result of this testing, I was able to demonstrateover 700 hours of life at “room-temperature” with virtually nochange in output power for such an uncoated laser diode [61].Even though this diode was not mounted in a sophisticatedpackage, and had over 14 AlGaAs–GaAs heterojunctions in theactive region, the reliability was shown to be suitable for manyapplications.

In September 1979, at the invitation of Dr. M. B. Panish, Ijoined the Physics Research Division of AT&T Bell Laborato-ries in Murray Hill, NJ. I was given some space (five “long-bays”) on the third floor of Building One to build a lab. I de-signed a lab for materials and device testing and a clean room labwith the gas services, exhaust scrubbers, and wafer cleaning fa-cilities to provide the necessary support to operate two MOCVDsystems. After a very long delay created by the construction ofthe clean room, I designed and built an entirely new MOCVDreactor. Except for the sealing of the base of the quartz growthchamber, this system used all-welded joints, stainless-steel bel-lows-sealed valves, and all metal-sealed components using ei-ther Cajon “VCR” face-sealed gas fittings or “Conflat” typemetal-sealed vacuum fittings. For the control system, I used dualTylan 16-channel programmers, which were a more advancedversion of the Tylan controller I had used at Rockwell. Further-more, the entire system was capable of being evacuated with aturbomolecular vacuum pump, which had a large-area liquid Ncold trap and quadrupole mass spectrometer attached to it. Thereactor system had the capacity for simultaneous operation ofeight metalorganic sources and four hydrides, including AsHand PH as well as the dopants HSe and SiH. The RF heated

chamber had a 2.5-in diameter susceptor that could hold one2.0-in diameter wafer. I again used all-welded 316 stainless steelmetalorganic source vessels that I designed and constructed forthis purpose. I also installed a Panametrics System I moisturemonitor and several probes in the H, AsH , and PH lines tomonitor these gases for water vapor content.

After this reactor was completed, it did not take long be-fore I had working laser devices. In fact, when I gave my de-vice technician, Phil Foy,20 the first AlGaAs–GaAs DH laserwafer I grew with this reactor to process into laser bars, heasked me “Will it lase?” and I told him “Of course!” It did!Later, in collaboration with B. Hartman and F. Nash in the LaserDevelopment Department (in Area 20), I worked on MOCVDlaser reliability. In May 1983, we submitted a paper describingthe first “high-reliability” MOCVD lasers [62]. These deviceswere graded-index separate-confinement heterostructure single-quantum-well lasers which exhibited degradation rate less than1%/kh at 70 C at 5 mW/facet CW output powers.

Later, I also grew InP-based materials in this reactor andstudied the lattice-matching of InGaAs and InGaAsP materials,as well as the doping and the growth of heterojunctions. Ieventually also made InGaAs–InP p-i-n photodetectors andInGaAsP–InP injection lasers.

IV. OTHER DEVELOPMENTS INMOCVD

The limitations of space and the specific subject of this paperhave prevented me from describing many of the other importantdevelopments leading to the breadth of the current MOCVDtechnology, among them, the development of low-pressure

20Philip W. Foy was William Shockley’s Technician in 1947 and was inWalter Brattian’s lab when Brattain first saw the “gain” of the first transistor.He is very skilled and experienced at making semiconductor laser devices,having worked on lasers for many years.

1048 IEEE JOURNAL ON SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 6, NO. 6, NOVEMBER/DECEMBER 2000

MOCVD for the growth of GaAs [63], InP [64], and InGaAsP[65], and the development of the “adduct-purification” schemefor the purification of metal alkyls [66]. Also, other workerssubsequently reported the MOCVD growth of injection lasers,including Veenvleitet al. in October 1978 [67], and Thrushetal. in March 1979 [68] Later, many other groups contributed tothe development of the MOCVD injection laser materials anddevice technologies.

Another important development is the use of advanced chem-ical kinetics, surface kinetics, and hydrodynamics models thatcan provide for solutions to the multifaceted boundary condi-tions occurring in a CVD system [69], [70]. The Sandia CVDSciences Group has provided tools for the detailed analysis ofMOCVD systems and they have contributed greatly to the un-derstanding of the large-area commerical MOCVD reactors incommon use today.

V. FUTURE VISION

The MOCVD process has been used for a wide variety ofIII–V binary, ternary, quaternary, and pentanary semiconductorfilms. It has also been used for the growth of oxides, super-conductors, dielectrics, and the deposition of metal films, in-cluding Cu for electrical interconnects. I expect that the usagein all these areas will increase dramatically in the next few years.One particularly important development is the expansion of theMOCVD growth of III–N materials, a process also pioneered byManasevit in 1971 [71]. This application of MOCVD will soonlead to the dramatic expansion of LED-based lighting prod-ucts into many of the “mass-market” lighting applications, in-cluding the development of high-efficiency white-light solid-state lamps.

It is clear that the future development of MOCVD will con-tinue to rely on improvements in the purity of precursors (bothorganometallics and hydrides). Furthermore, advances in theunderstanding of chemical reactions, hydrodynamics, precursorkinetics, etc., should lead to improved large-scale reactor de-signs capable of growing simultaneously on more than a dozen6-in diameter substrates using a wide range of growth pressures.Furthermore, the efficiencies of scale in the production of metalalkyls should permit the cost factor of precursors to be reduced.MOCVD reactors with kilogram quantities of metal alkyls arenow common in production environments.

One important aspect of MOCVD (and all other CVD epi-taxial growth processes, including CVD for Si) that still re-mains to be developed is “real-time monitoring and process con-trol”—while somein situ monitoring techniques have been de-veloped, most notably spectroscopic ellipsometry, spectrally re-solved reflectivity, and emissivity-corrected pyrometry. Thesetechniques permit some useful degree of “real-time monitoring”but the missing element—the “real-time control” is still sorelyneeded. One important component to this control loop is themonitoring of the gas-phase and surface species. Techniques fordetermining gas-phase composition are well established and in-clude laser-induced fluorescence and absorption spectroscopy.The measurement of surface species in a CVD environment isstill problematical. Additional complications arise due to thelack of spatial uniformity in the gas phase inside a reactor and

near the growing surface. Real-time three-dimensional chemicalmapping of the reactant species inside a CVD growth chamber isa daunting problem and one that will not yield easily using con-ventional techniques. Many more years of research and devel-opment are required to realize a true “process control” systemfor MOCVD. However, it is an area of continued activity and re-search results are being continually translated into commercialproducts.

VI. SUMMARY AND CONCLUSION

In the late 1970s, MOCVD was shown to be a viabletechnology for the growth of high-performance solar cells andsophisticated injection lasers. From this work, it was possible topredict that the MOCVD process would become an importantelement in the fabrication of a wide variety of high-perfor-mance semiconductor devices. Because of the economicsand flexibility of the process, the quality of the materialsproduced, and the scalability of the technology, it has come todominate the epitaxial growth of III–V semiconductors. Thedemonstration of the first room-temperature CW quantum-wellinjection lasers (grown by MOCVD) was a watershed eventthat changed the course of III–V materials technology foroptoelectronics and also for electronics. Today, most opticalmemory systems, (e.g., CD-ROMs, DVD players, etc.) andoptical communications systems employ such QW injectionlasers based upon MOCVD epitaxial films. In addition, mosthigh-performance digital cellular communications rely onthe performance of MOCVD-grown heterojunction bipolartransistors. In the near future, MOCVD will play a dominantrole in the lighting market, making MOCVD a “householdmaterials technology”—but probably not a “household word.”I remember when explaining the laser device results I haddemonstrated using the MOCVD process to one of the VicePresidents at Rockwell, he told me that he was impressed withthe results I had achieved using “metal oxide CVD.” I toldhim that it had taken quite some effort to “get the oxide outof MOCVD!” Somehow “MO” is always thought of as “metaloxide” … perhaps someday the “metalorganic” term will bewidely known as well.

ACKNOWLEDGMENT

The author would like to thank Dr. J. Mee for the supportand encouragement in the early stages of this work at Rock-well, and Dr. R. P. Ruth who was the Principal Investigator ofthe ERDA contract. The author also would like to thank Dr. H.M. Manasevit for being very helpful in the beginning phases ofhis MOCVD research and W. I. Simpson for many useful dis-cussions. It is the author’s pleasure to thank many individualswho were directly involved in supporting this research. D. Yin-gling was involved in the MOCVD growth of “low-cost” solarcells, and L. A. Moudy provided X-ray characterization of someof the AlGaAs–GaAs materials. Dr. J. J. J. Yang helped in theelectrical characterization of some of the films grown at Rock-well. F. Kinoshita provided help in metallization of the wafers.

Prof. N. Holonyak, Jr., was instrumental in the initiation ofand the beginning phases of the work on quantum-well lasers

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and has always been an excellent collaborator and role modelto the author for more than thirty years. The training and ex-perience received in Holonyak’s lab regarding the approach tosolving problems has been useful throughout the author’s career.The author also wants to thank some of N. Holonyak’s previousgraduate students who helped with the early QW laser work,particularly, Dr. R. Chin, Prof. R. M. Kolbas, Dr. W. D. Laidig,Dr. E. A. Rezek, and Dr. B. A. Vojak.

Several people at Bell Labs were also instrumental in sup-porting the work on reliable MOCVD AlGaAs–GaAs lasers, inparticular, Dr. M. B. Panish, Dr. V. Narayanamurti, and Dr. J.A. Giordmaine. The author also wants to thank his collabora-tors Dr. R. L. Hartman, Dr. R. C. Miller, Dr. F. R. Nash, Dr. J.van der Ziel, and acknowledge the excellent technical support ofP. W. Foy, R. B. Zetterstrom, and J. R. Velebir. Finally, the au-thor wants to thank his wife, D. E. Dupuis, and his daughter, E.A. Dupuis, for their strong support and encouragement over thepast years of hard work and during the many nights and week-ends that he had been “MIA” at home (or “AWOL”) because hewas in the laboratory.

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[20] H. M. Manasevit and Rockwell International Corp., “Epitaxial com-posite and method of making,” U.S. Patent 4 368 098, Jan., 11 1983.

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[24] J. A. Arthur, “Vapor pressures and phase equilbria in the Ga-As system,”J. Phys. Chem. Solids, vol. 28, p. 2257, 1967.

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[44] E. A. Rezek, N. Holonyak, Jr., B. A. Vojak, G. E. Stillman, J. A. Rossi,D. L. Keune, and J. D. Fairing, “LPE In Ga P As (x � 0:12,z � 0:26) DH laser with multiple thin-layer (<500 Å) active region,”Appl. Phys. Lett., vol. 31, no. 288–290, 1977.

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[49] G. B. Stringfellow and H. T. Hall, Jr., “VPE growth of AlGa As,”J. Cryst. Growth, vol. 43, pp. 47–60, 1978.

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[51] N. J. Nelson, K. K. Johnson, R. L. Moon, H. A. Vander Plas, and L. W.James, “Organometallic-sourced VPE AlGaAs–GaAs concentrator solarcells having conversion efficiencies of 19%,”Appl. Phys. Lett., vol. 32,no. 1, pp. 26–27, 1978.

[52] N. Holonyak Jr., R. M. Kolbas, R. D. Dupuis, and P. D. Dapkus,“Room-temperature continuous operation of photopumped MO-CVDAl Ga As–GaAs–GaAs–AlGa As quantum-well lasers,”Appl.Phys. Lett., vol. 33, no. 1, pp. 73–75, 1978.

[53] R. D. Dupuis, P. D. Dapkus, N. Holonyak, Jr., E. A. Rezek, andR. Chin, “Room-temperature laser operation of quantum-wellGa Al As–GaAs laser diodes grown by metalorganic chemicalvapor deposition,”Appl. Phys. Lett., vol. 32, no. 5, pp. 295–297, 1978.

[54] N. Holonyak, Jr., R. M. Kolbas, W. D. Laidig, B. A. Vojak, R. D.Dupuis, and P. D. Dapkus, “Low-threshold continuous laser op-eration (300–337K) of multilayer MO-CVD AlGa As–GaAsquantum-well heterostructures,”Appl. Phys. Lett., vol. 33, no. 8, pp.737–739, 1978.

[55] R. D. Dupuis, P. D. Dapkus, R. Chin, N. Holonyak, Jr., and S. W.Kirchoefer, “Continuous 300K laser operation of single-quantum-wellAl Ga As–GaAs heterostructure diodes grown by metalorganicchemical vapor deposition,”Appl. Phys. Lett., vol. 34, no. 4, pp.265–267, 1979.

[56] B. A. Vojak, N. Holonyak, Jr., R. Chin, E. A. Rezek, R. D. Dupuis, andP. D. Dapkus, “Tunnel injection and phononassisted recombination inmultiple quantum-well Al Ga As–GaAs p–n heterostructure lasersgrown by metalorganic chemical vapor deposition,”Appl. Phys., vol. 50,no. 9, pp. 5835–5840, 1979.

[57] R. D. Dupuis and P. D. Dapkus, “Single-longitudinal-mode cw room-temperature Ga Al As–GaAs channel-guide lasers grown by met-alorganic chemical vapor deposition,”Appl. Phys. Lett., vol. 33, no. 8,pp. 724–726, 1978.

[58] , “Room-temperature operation of distributed-Bragg-confinementGa Al As–GaAs lasers grown by metalorganic chemical vapor de-position,”Appl. Phys. Lett., vol. 33, no. 1, pp. 68–69, 1978.

[59] R. D. Dupuis, L. A. Moudy, and P. D. Dapkus, “Preparation and prop-erties of Ga Al As–GaAs heterojunctions grown by metalorganicchemical vapor deposition,” presented at the Seventh Int. Symp. GaAsRelated Mater., St. Louis, MO, Sept. 24–27, 1979.

[60] R. D. Dupuis, R. L. Hartman, and F. R. Nash, “Facet-coated graded-index separate-confinement-heterostructure single-quantum-well lasershaving low degradation rates, (<1% KH) at 70 C,” IEEE Electron De-vice Lett., vol. EDL-4, no. 8, pp. 286–288, 1983.

[61] R. D. Dupuis, “700 h continuous room-temperature operation ofAl Ga As–GaAs heterostructure lasers grown by metalorganicchemical vapor deposition,”Appl. Phys. Lett., vol. 35, no. 4, pp.311–314, 1979.

[62] R. D. Dupuis, R. L. Hartman, and F. R. Nash, “Facet-coated graded-index separate confinement-heterostructure single-quantum-well lasershaving low degradation rates (<1 Percent/kh) at 70C,” Appl. Phys.Lett., vol. EDL-4, no. 8, pp. 286–288, 1983.

[63] J. P. Duchemin, M. Bonnet, F. Koelsch, and D. Huyghe, “A new methodfor growing GaAs epilayers by low pressure organometallics,”J. Elec-trochem. Soc., vol. 126, no. 7, pp. 1134–1142, 1979.

[64] J. P. Duchemin, M. Bonnet, G. Beuchet, and F. Koelsch, “Organometallicgrowth of device-quality InP by cracking of In(CH ) and PH atlow pressure,” inGallium Arsenide and Related Compounds—1978. ser.Inst. Phys. Conf. Ser. no. 45, C. M. Wolfe, Ed. Bristol: Institute ofPhysics, 1979, ch. 1, pp. 10–18.

[65] J. P. Duchemin, J. P. Hirtz, M. Razeghi, M. Bonnet, and S. D. Hersee,“GaInAs and GaInAsP materials grown by low pressure MOCVD formicrowave and optoelectronic applications,”J. Cryst. Growth, vol. 55,pp. 64–73, 1981.

[66] A. C. Jones, “Metalorganic precursors for vapor phase epitaxy,”J. Cryst.Growth, vol. 129, pp. 728–773, 1993.

[67] H. Veenvleit, W. J. Bartels, and C. v. Opdorp, “VPE growth and analysisof GaAs–AlGaAsP double heterostructure laser structures,” presentedat the 1978 IEEE Int. Semiconductor Laser Conf., San Francisco, CA,Oct. 30–Nov. 1, Paper E3.

[68] E. J. Thrush, P. R. Selway, and G. D. Henshall, “Metalorganic CVDgrowth of GaAs–AlGaAs double heterojunction lasers having low in-terfacial recombination and low threshold,”Electron Lett., vol. 15, pp.156–158, 1979.

[69] M. E. Coltrin, R. J. Kee, and J. Miller, “A mathematical model of thecoupled fluid mechanics and chemical kinetics in a chemical vapor de-position reactor,”J. Electrochem. Soc., vol. 131, no. 2, pp. 425–434,1984.

[70] R. J. Kee, G. H. Evans, and M. E. Coltrin, “Application of supercom-puters to modeling fluid transport and chemical kinetics in chemicalvapor deposition reactors,” inAmer. Chem. Soc. Symp. Series, vol. 353,1987, p. 334.

[71] H. M. Manasevit, F. M. Erdman, and W. I. Simpson, “The use of metalor-ganics in the preparation of semiconductor materials—IV: The nitridesof aluminum and gallium,”J. Electrochem. Soc., vol. 118, no. 11, pp.1864–1868, 1971.

Russell D. Dupuis(S’68–SM’84–F’87) received thePh.D. degree in electrical engineering from the Uni-versity of Illinois, Urbana-Champaign, in 1973.

He currently holds the Judson S. Swearingen Re-gents Chair in Engineering and is Professor in theDepartment of Electrical and Computer Engineeringand in the Microelectronics Research Center at TheUniversity of Texas at Austin. He worked at Texas In-struments, Dallas, TX, from 1973 to 1975. In 1975,he joined Rockwell International, where he was thefirst to demonstrate that MOCVD could be used for

the growth of high-quality semiconductor thin films and devices. He joinedAT&T Bell Laboratories in 1979, where he extended his work to the growthof InP-InGaAsP by MOCVD. In 1989, he joined The University of Texas atAustin as a Chaired Professor. His technical specialties include semiconductormaterials and devices, epitaxial growth by MOCVD, and heterojunction struc-tures in compound semiconductors. He is currently studying the growth of III–Vcompound semiconductor devices by MOCVD, including materials in the In-AlGaN–GaN, InAlGaAsP–GaAs, and InAlGaAsP–InP systems.

Dr. Dupuis is a member of the NAE and a Fellow of the OSA.