Integration Of Microelectronics Based Unit Operations Into ... · modules are intended to reinforce...

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Proceedings of the 2003 American Society for Engineering Education Annual Conference & ExpositionCopyright © 2003, American Society for Engineering Education

Integration of Microelectronics-Based Unit Operations into theChE Curriculum

Milo D. Koretsky, Chih-hung (Alex) Chang, Sho Kimura, Skip Rochefortand Cyndie Shaner

Department of Chemical EngineeringOregon State University

Corvallis, OR 97331-2702

AbstractHistorically, chemical engineering has been focused on petrochemical and bulk chemicalproduction. However, over the last 10-15 years, more chemical engineers and chemicalengineering opportunities for new graduates have moved into the microelectronics industry.This is especially true in Oregon and at Oregon State University (OSU), where approximately60% of the B.S. and M.S. graduates in the last five years have been employed in some sectors ofthe microelectronics and related industries. A number of schools have started to incorporatemicroelectronic processing into their curriculum. For the most part, this material tends to bepresented in specialized, elective courses. However, when presented in the context of corechemical engineering courses, these unit operations can provide students with depth as well asbreadth knowledge. The chemical engineering department at OSU is committed to developingstrength in microelectronics processing within the context of the fundamental skills of thediscipline. To this end, we are developing curricular and experimental modules from selectedunit operations common in the microelectronics industry, and are integrating these into theclassroom and the laboratory. Unit operations include: plasma etching, spin coating, chemicalvapor deposition, electrodeposition and chemical mechanical planarization. The curricularmodules are intended to reinforce core ChE fundamentals with examples from microelectronicsprocessing. The lab modules provide students with hands-on learning in this area as well asmore open-ended problem solving experiences. The incorporation of these microelectronics unitoperations into core engineering science classes, into senior lab and into process design will bepresented.

1. IntroductionThe semiconductor industry has grown rapidly in the last three decades. The chemicaltechnologies have played a central role in this continuing evolution. Historically, chemicalengineering has been focused on petrochemical and bulk chemical production. However, moreand more chemical engineers are working in the microelectronics and related industries. Forexample, the most recent AIChE placement survey shows that from 1997 to 1998 the number ofBS graduates placed in the electronics industry increased over 50% from 7.0% of BS graduatesto 11.4%. The percentage of ChE graduates hired into this industry with advanced degrees is

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even larger1. Chemical engineers have the advantage of a solid background in chemical kinetics,reactor design, transport phenomena, thermodynamics and process control to undertake thechallenges in microelectronics processing. Many chemical engineering pioneers in this field haverecognized this ability2,3. A number of schools have started to incorporate microelectronicprocessing into their curriculum. For the most part, this material tends to be contained in surveycourses that are descriptive. However, when presented in the context of core chemicalengineering science, these unit operations can provide students with depth as well as breadth.An example of such an approach is the incorporation of thermal oxidation of silicon into the unitoperations lab at Georgia Tech4.

Additionally, development of education programs in this area has led to innovative and improvededucational practices. A successful example is the curriculum developed by the chemical andmaterials engineering department at San Jose State University (SJSU). The essence of theirproject is to abandon the traditional laboratory cookbook instruction method and create a team-oriented and open-ended laboratory where students develop the same types of skills they willlater use in industry. The content of their laboratory includes having students make a field effecttransistor and perform open-ended experiments to improve this process5. While the approach atSJSU relies on the coordination between students in three different disciplines (EE/MatE/ChE),we are implementing the same type of learning environment solely within ChE at OSU. In thisway, we can leverage off the fundamental research in microelectronics processing to developunit operations accessible to undergraduate students based on their core engineering sciencebackground.

The integration of unit operations in microelectronics has occurred in conjunction with atransformation in the Senior Unit Operations Laboratory that has begun during the 2000-2001academic year. A newly created Endowed Chair, the Linus Pauling Engineer, was hired fromindustry to identify and incorporate the highest priority professional practices to senior lab. Sheserves as “project director” for this class to help new graduates become immediately prepared forindustrial practice. Thus the unit operations lab provides students with the array of skills theywill need to perform effectively in industry. The ChE Unit Operations Laboratory inMicroelectronics Processing is targeted at undergraduate students who are interested in careers asprocess engineers in microelectronics and related industries. The students will both develop anin-depth understanding of the underlying physical and chemical principles in unit processescommonly used in microelectronics and related industries and also acquire the needed “softskills” to be successful.

2 Microelectronics Unit Operations2.1 OverviewHundreds of individual process steps are used in the manufacture of even simplemicroelectronics devices. However, the fabrication sequence uses many of the same unitprocesses numerous times. A list of unit operations that are common for the fabrication ofmicroelectronics devices is given in Table 1. These unit operations rely on core chemicalengineering science. The curricular material that is related to each topic is also illustrated inTable 1. Modules of the following unit operations will be developed for integration into thechemical engineering curriculum and unit operations laboratory at OSU. P

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1. Plasma Etching2. Chemical Vapor Deposition3. Spin Coating4. Electrochemical Deposition5. Chemical Mechanical Planarization

These unit operations contain complex systems that involve the interaction of many physical andchemical processes. Fortunately there have been extensive research efforts in these areas, andmany of the fundamental mechanisms have been elucidated. For example, plasma etchingprocesses have been modeled based on the fundamental transport and reaction processesoccurring within the glow discharge to understand issues of etch rate, selectivity, uniformity andprofile 6-9. Similarly chemical vapor deposition reactors have been modeled in analogy to porouscatalysts, incorporating transport and reaction processes10-12. Control schemes have been basedon these fundamental reactor models13. The fluid dynamics of spin coating of photoresist hasbeen modeled and studied experimentally to predict coating thickness and uniformity as afunction of spin-speed, fluid properties and spin duration14-17. Similarly, fluid dynamics basedmodels of chemical mechanical planarization are being developed18-22. However, when theseunit operations are covered at the university, they are usually taught in survey courses andapproached descriptively and phenomenologically, rather than applying the fundamentalengineering sciences depicted in Table 1.

Table 1. Unit Operations in Microelectronic Device Fabrication

Unit Operations Chemical EngineeringCore Courses

Unit Operations Chemical EngineeringCore Courses

Bulk Crystal Growth fromMelt

Fluid DynamicsHeat TransferMass TransferThermodynamicsReaction EngineeringProcess Control

Lithography Photoresist spin coating Photoresist baking Photoresist exposure and

development

Fluid DynamicsMass TransferPolymer RheologyKineticsProcess Control

Surface Reactions Cleaning

Oxidation

KineticsFluid DynamicsMass Transfer

Doping and DopantRedistribution Ion implantation Thermal diffusion

Mass TransferHeat TransferProcess Control

Etching Plasma Etching Wet Etching

Mass TransferKineticsReaction EngineeringProcess Control

Thin Film Deposition Physical Vapor Deposition Chemical Vapor Deposition Electrochemical Deposition

KineticsFluid DynamicsMass TransferHeat TransferThermodynamicsElectrochemical

EngineeringReaction EngineeringProcess Control

Planarization Chemical Mechanical

Fluid DynamicsMass TransferElectrochemical

EngineeringProcess Control

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2.2 Integration of microelectronics unit operations into the OSU ChE curriculumWe are synthesizing the research results in the literature and applying them to the five unitoperations discussed above to make them accessible to undergraduate chemical engineers while,at the same time, reinforcing the fundamental engineering science taught in the curriculum. Toaccomplish this objective, we are developing both lab based and class room based instruction.

Integration into the lab occurs through the two required Unit Operations Laboratories (ChE 414and 415) as well as a ChE elective, Thin Film Materials Processing (ChE 444). The first quarterof the two-quarter senior lab sequence (ChE 414) is highly structured and focuses on the studentscompleting 3 unit operation experiments. We intend to have each student complete at least 1microelectronics unit operation during this rotation. Due to unforeseen circumstances, the targetfor integration into ChE 414 has been postponed until W 2004. This second quarter of the seniorlab course (ChE 415) builds on the work done in UO Lab 1. The focus is on workingindependently, developing a project proposal, completing experimental work and writing a finaltechnical memorandum that includes recommendations for future work. The microelectronicsunit operations are designed to be flexible enough so that each year, the group of students has anew, unique, and creative experience. The first four unit operations listed above were integratedinto ChE 415 in S 2002. They will be described later in the paper. It is intended to provide labin chemical mechanical planarization in S 2003. In addition students interested in pursuing hightech careers usually take Thin Film Materials Processing (ChE 444). In fact, this course isrequired for both the Microelectronics Processing and the Materials Science and Engineeringoptions in the ChE department at OSU. Starting W 2003, ChE 444 has been expanded from 3credits to 4 credits and now includes a lab. In the lab, students will be introduced to the unitoperations listed above, albeit in a well-prescribed manner.

Class room examples are being developed based on the labs at OSU as well as the researchliterature. Each of the four Unit Operations listed above will include at least two exampleexercises or homework problems to be integrated into a core chemical engineering science ordesign course. By integrating the technical content in this manner, the future process engineersin this industry will be able to draw upon core fundamentals as they go about problem solving. Agrid of target courses for classroom integration is presented in Table 2. Those marked with an“X” represent targeted courses. For example, the design problem offered in Process Design II(ChE 432) in S 2002 is shown in Figure 1.

In addition to reinforcing fundamental chemical engineering sciences through these selectedmicroelectronic processing unit operations, we will also address several other ABET criteria.Our goal is that every student has mastered both the technical skills and professional practicesnecessary to be successful. Professional practices to be incorporated include effective oral andwritten communications, project planning, time management, interpersonal interaction,teamwork, and proactive behavior. This is an area of weakness in engineering education. Thenewly endowed Linus Pauling Engineer serves “project director” for all student teams. Shecoordinates the professional practices learning exercises, the physical facilities and the executionof team projects.

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Table 2. Implementation grid of microelectronics unit operations and OSU ChE classes

OSU ChE CoursePlasmaEtching

ChemicalVapor

Deposition

SpinCoating

ElectrochemicalDeposition

ChemicalMechanicalPolishing

ChE 211 Materials Balances X XChE 212 Energy BalancesChE 302 Chemical Process Statistics XChE 311 Thermodynamic Properties and

RelationshipsX X

ChE 312 Phase and Chemical ReactionEquilibrium

X X X

ChE 323 Applied Momentum and EnergyTransfer

X

ChE 414 Chemical EngineeringLaboratory

X X X

ChE 415 Chemical EngineeringLaboratory

X X X X

ChE 431 Chemical Plant Design XChE 432 Chemical Plant Design XChE 443 Chemical Reaction Engineering X X XChE 444 Thin Film Materials Processing X X X X XChE 445 Polymer Engineering and

ScienceX

Figure 1. CVD Design problem assigned S 2002.

Reactor DesignChE 432 Detailed Design Project -LPCVD Silicon Nitride

Spring, 2002

Introduction

This project is designed for senior students in ChE 432, who are interested inexperiencing a detailed design/simulation project in microelectronics processing. Thetopic selected is LPCVD (Low Pressure Chemical Vapor Deposition) that has been usedfor the deposition of silicon nitride on silicon wafers in the process for producing ICs.

Requirements

Students who work on this project are required to:

(1) propose a design idea for a piece of equipment that handles 200 siliconwafers of 300mm in diameter, based on which

(2) develop a model to simulate the performance of the equipment, and

(3) determine proper operating conditions, i.e. temperature distributions, operatingpressure, feed rates, and reaction time for controlling the deposit thickness at 1000 with variations across wafers and from wafer to wafer within ±3%. P

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2.3 Plasma EtchingGlow discharge plasmas are used for a variety of surface manufacturing applications especiallyin integrated circuit manufacturing where up to 30% of all process steps involve plasmas in oneway or another. A plasma barrel etcher has been incorporated into projects in the UnitOperations Laboratory (ChE 415) and Thin Film Materials Processing (ChE 444/544). Thisplasma barrel etcher unit and supporting systems were donated from Intel. In the barrel etcher,ion bombardment is suppressed since the substrate holder is contained within a Faraday cage.Thus, the etch rate depends on the concentrations of free radicals that react at the substratesurface. Uniform etching only occurs when mass transport to the surface is much greater thanthe inherent reaction rate. By measuring the etch as a function of radial position the relativeimportance of mass transfer to surface reaction can be backed out. The variation of etch rate as afunction of the sample radius would allow students to interpret etch data in terms of fundamentalchemical engineering principles. Industrially, obtaining uniform etching rate is also a centralproblem in plasma etching reactor design. Other examples of student lab experiments include thefollowing: finding optimal process settings for etching polyphenylene oxide materials using SF6

and O2 feed gases using Design of Experiments (DOE) and analyzed using well-mixed reactormodel; the effects of wafer spacing on etch rate; the effect of the number of substrates, i.e.,loading, on etch rate; transient analysis of temperature effects on the etching rate.

In Spring 2002, two groups of three students were given an assignment to develop a processwhich minimized interwafer as well as wafer to wafer variation in etch rate. This lab includedseveral processes to pattern and then etch a wafer, including cleaning, spin coating,photolithography and plasma etching. Additionally students developed their own art-work toserve as a mask in photolithography. However, the experimental design focused on etchingparameters while the other processes were unchanged. One group did a 2x2 design in whichthey varied pressure and wafer spacing while the other group varied power and spacing.Thickness measurements before and after etching were made using a profilometer.

Both groups ably implemented statistics into the design and analysis of this project, using linearregression and ANOVA. On group even recognized the need for a gauge study to test themeasurement precision of film thickness. They also learned about the difficulties of running acontrolled experiment in a processing environment. One illustrative story tells of contaminateddeveloper by another class using the lab ruining a run. The plasma reactor does not havetemperature control. Thus the temperature rises as power is input during the etch process. Thisfacet provided a good opportunity to use ChE analysis to understand the system. The studentgroup was advised to record temperature during the process, but needed faculty help to developan averaging method based on the Arrhenius expression for the activated process.

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Figure 2. Plasma barrel etcher and schematic

2.4 Chemical Vapor DepositionIn this module, the gas-solid reaction kinetics are elucidated through real-time rate measurementsusing a modified thermogravimetric analyzer (TGA). Students can measure an increase in massof silicon wafer sample specimen (about 10 mm by 20 mm) with time, resulting from thedeposition of silicon nitride at different reactant concentrations and reaction temperatures atatmospheric pressure. Inert argon is mixed with the two gaseous reactants (ammonia anddichlorosilane). Since the reaction is at atmospheric pressure, as opposed to vacuum, studentsmust account for the effect of resistance to diffusion through the gas film on silicon surface andfind ways to eliminate the mass-transfer effects. In this context, they are asked to discuss thedifference between the low pressure CVD and atmospheric pressure CVD. The kinetics obtainedusing the modified TGA will further be integrated into senior capstone design via designing aCVD reactor and simulating its performance for achieving uniform film thickness. Students willbe challenged to develop a simple mathematical model that incorporates the fluid-flow,diffusion, and reaction that take place simultaneously. Students will use the model to predict thegrowth of silicon nitride films on two hundred 300mm diameter wafers varying withtemperature-profile settings, reactant feed rates, operating pressures.

Plasma Glow

Reactor

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Figure 3. Silicon nitride CVD reactor and schematic

In Spring 2002, a group of three students were given the assignment to establish a kineticexpression for the atmospheric pressure silicon nitride CVD reactor. Their expectations over afour-week period given for collecting data, in addition to professional practices described later,included:

1. To design an experiment to cover three temperatures in a range from 600°C to 800°Cand concentrations of dichlorosilane < 0.10 mole% and ammonia < 0.30 mole%

2. To estimate the magnitude of mass transfer resistance and compare it to thedeposition rate

3. To analyze and interpret data4. To represent the silicon nitride deposition rate in terms of dichlorosilane and

ammonia concentrations as well as temperature5. To discuss possible mechanism for the atmospheric pressure silicon nitride CVD and

differences from LPCVD

The students changed the concentration of ammonia and maintained that of dichlorosilaneconstant because of time constraints. On the other hand, they did collect data at three differenttemperatures. However, the data collected at the highest temperature they selected showeddifferent tendencies from the data collected at the other two lower temperatures. Therefore, theydid not try to establish any consistent temperature dependency of deposition rate and insteadexplored why their data at the highest temperature were different. Also, their data showedroughly a 1/3-order dependency on the ammonia concentration. They needed assistance from theinstructor to interpret this tendency in terms of a Langmuir-Hinshelwood rate expression. Theyalso estimated the mass transfer rate under their experimental conditions and compared itsmagnitude to the deposition rate to conclude that their data were free from the mass transfer

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resistance. However, they needed assistance from the instructor to understand the theoreticalbackground for the mass transfer mechanism on a flat plate of silicon wafer in terms of theboundary-layer theory.

2.5 Spin CoatingSpin coating has come into widespread use in the microelectronics industry for coating thephotoresists used to define patterns in the films on a silicon wafer. It will also be used in futuretechnologies as polymers become incorporated as dielectrics materials. The underlying principlesof spin coating (fluid flow, fluid properties, surface phenomena) and the process itself make it anatural for inclusion in the chemical engineering curriculum. The precursor to coating, surfacewetting and adhesion, is also a classical problem. The spin coating of solid substrates withviscous liquids and surface wetting phenomena (surface tension, contact angle, viscosity) is doneusing a “state-of-the-art” programmable laboratory spin coater from Specialty Coating Systems(SCS Model P6700) and highly polished and oxide coated 6” silicon wafers. Examples ofengineering projects include: experiments on viscous, Newtonian liquids to test the Emsliemodel; comparing data to published spin coating results for Newtonian liquids14; and coatingphotoresist on silicon wafers as the first step in the photolithography process. In S 2002, thisexperiment was used in support of the Plasma etching studies.

Figure 4. Spin coater and flow schematic

2.6 Electrochemical DepositionThe electrochemical deposition system includes a computer-controlled bipotentiostat, PineChemsoftware, rotator, electrodes, and a standard voltammetry cell. A variety of experiments could bedesigned using this system. Examples of such experiments are: diffusion coefficient

from “Boundary Layer Theory”

H. Schlichting and K. Gersten8th Ed. Springer, 2000.

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determination by rotating electrode cyclic voltammetry; measurement of the kinetics and the fluxof copper ions to an electrode surface by means of rotating ring-disk electrode; study of masstransfer using rotating electrodes; the effects of additives on deposition rates; leveling effects ofadditives; superfilling phenomena, and resistive seed effect etc.

Figure 5. Copper electrodeposition reactor and schematic

In Spring 2002, the student team was taught how to use this system by going through a“cookbook” experiment using cyclic voltammetry and the rotated disk electrode to characterizethe redox reaction of potassium ferricyanide solution. After the training, they were asked topropose an experimental plan using this setup. They decided to study the copper mass transportusing different copper electrolyte (CuCl2 and CuSO4) and the influence of sulfur containingadditive (thiourea). The experiments were performed using acid copper solutions prepared fromCuCl2 and CuSO4 with and without thiourea. The electrochemical reactions were characterizedby sweeping the voltage and measured the current. The boundary layer thickness was controlledby the rotating speed of the working electrode and the Levich equation was used to determine the P

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diffusivity. Currently, we are considering building an industrial type fountain-plating cell tocomplement this setup.The students got more and more enthusiastic about the project. This is largely attributed to: 1.their creative ownership of this project on their own and 2. the discovery. One difficulty inrunning the lab is how to implement the “cooking without recipe” spirit without losing thetechnical content. Technically, they learned the basic principle and terminology about copperelectrodepostion from doing the lab and a literature review. The lab also provided an opportunityto apply what they have learned in the ChE core courses including: boundary layer theory, masstransport, and surface limited vs. reaction limited reaction. The question and answer section inthe oral presentation has challenged the students to think more deeply and independently.

2.7 Chemical Mechanical PlanarizationThe experimental set up of a bench scale CMP module is shown in Figure 6. The experimentalset up is adopted from the research literature23, which has been shown as a useful tool forunderstanding of the reaction mechanisms during CMP. In this set up, the copper CMP will bestudied in a three-electrode electrochemical cell by using a copper-plated rotating disk electrode.The polishing downward force will be measured by a balance, which supports the entireelectrochemical cell. The DC electrochemical measurement will be carried out by using apotentiostat. A variety of experiments can be designed to study the Cu CMP process. Forexample, the effect of HNO3 or NH4OH on the chemical etching mechanism, the effects ofadditives (e.g. inhibitor, oxidizer), the relation between downforce and removal rates throughthe Preston equation. The Preston equation relates removal rate to driving force in the same waythat mass transfer coefficients relate mass transfer to driving force. Studies on the bench scalesystem will be scaled up to the industrial scale system shown in Figure 7.

Figure 6. Bench scale CMP reactor and schematic

Polishing Pad

Computer Controlled Potentiostat

Counter Electrode

Rotating Disk Electrode( Working Electrode)

Weighting Balance

Reference Electrode

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Figure 7. Industrial scale CMP reactor

3. Professional PracticesThe Linus Pauling Engineer position was established November 2000 with the primary objectiveto incorporate professional practices into the Chemical Engineering curriculum so that graduatesare immediately ready for professional practice. The initial focus of the new position was theSenior Unit Operations Laboratory course sequence taught during the winter and spring quartersof the school year. Opportunities for integrating the content throughout the curriculum are nowbeing identified. For the first year two individuals with extensive industry experience wereresponsible for the course and its design. Building on the strong technical content of prior years,the team identified key professional practices that needed to be taught and developed modulesand assignments so that the students could learn and practice these professional practices duringthe laboratory sequence.

Professional practices are incorporated into the Senior Unit Operations Laboratory throughlectures, class work assignments and homework assignments. Eight lectures cover projectmanagement, meeting skills, technical writing, oral presentations, safety, rational managementprocesses (situational, problem, decision and potential problem analysis), personality self-assessment and conflict resolution. All students complete writing assignments and oralpresentations to practice the professional skill as well as demonstrate technical understanding ofthe unit operation. The instructor, the student and the student’s peers assess each student’s workprocess skills, safety performance and team behaviors.

The following professional practices have been incorporated into the Senior Unit OperationsLaboratory. The key mode for delivering the course material to the students is instruction withexperiential learning.

1. Writinga. Formal technical reports following the technical journal format (One individual

and two team reports)b. Safety report for supervisor and peers (One individual)c. Operations Manual for a non-technical audience (One individual)

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d. Weekly Status Reports for supervisor (Two individual)e. Project Proposal for management team (One team)f. Technical Memorandum for supervisor (One team)

2. Oral Presentationsa. Formal 30-minute presentation using MS PowerPoint with a computer and

computer projector followed by questions from faculty subject “experts” andpeers.

b. Informal presentations including impromptu report outs from team exercises andleading team meetings using formal meeting processes.

3. Project Managementa. Introduction: each student prepares a list of deliverables and detailed task list for

one unit operation experiment during the first quarter of the sequence. Theyprepare a Gantt chart using MS Project to document their plan.

b. Application: each student team prepares a project plan in the Gantt chart formatusing MS Project for the entire second quarter covering the three phases of theproject: Project Proposal, Experimentation, and Final Report andRecommendations.

4. Formalized Meeting Processesa. The instructor role models the use of a formal meeting process including: Desired

Outcomes, Agenda and Audit for all lecture periods.b. The student teams must prepare Desired Outcomes, an Agenda and do an Audit

for all lab sessions. The instructor reviews these and participates in all audits.Focus is effective time utilization and looking for ways to improve.

5. Rational Thinking Processesa. The instructors developed this module based on the work by Kepner and Tregoe

in their book, The New Rational Manager24. The processes include problemanalysis, decision analysis, potential problem analysis and situational analysis.

b. The module includes a lecture on each of the four processes including an exampleof how to use the process. The students are given a homework assignment on acase study for each process. They are expected to use the specific process for thecase study to complete the homework assignment.

c. They are encouraged to use the processes in their laboratory work; for example,they must prepare a potential problem analysis as part of the Project Proposal forthe second quarter of the series.

6. Team and Personal Effectivenessa. During the first quarter of the series, the three person teams rotate through three

jobs. These jobs are team leader, safety coordinator and operations coordinator.Each job has specific responsibilities. They learn the value of dividing the workto more effectively use their time.

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b. The Myers-Briggs self-assessment tool is given and a lecture is delivered talkingabout personality types, their preferences and how it impacts team behaviors. Atheme of valuing diversity is maintained throughout the course sequence.

c. The instructor developed a module on Conflict Resolution based on the Thomas-Kilman Conflict Mode self-assessment tool and a workshop module developed byConsulting Psychologists Press, Inc. The students complete their self-assessmentand then a series of 4 lectures including role-playing are used to teach the studentsabout the skills, correct use, impact of overuse and impact of under use of the 5modes.

d. Each student completes a peer review of his or her teammates during each of thequarters. This along with the instructor review of individual and teamperformance is a significant part of the students’ final grade (10% first quarter and20% second quarter).

7. Safety PracticesThe instructors developed a module teaching the students the seven elements of asafety plan. These include hazardous materials, facilities, safe behaviors,emergency response, training, auditing, and record keeping. The safetycoordinator is responsible for preparing a safety plan specific to the experimentbased on these seven elements. They must train their teammates, audit theirbehaviors and keeps records of the training and audits. All safety activity isdocumented in a written safety reporta.

8. Concepts of Continuous ImprovementThe concept of continuous improvement is integrated in all aspects of the courseconcept through the use of audits. The audit reviews whether desired outcomeswere achieved and then reviews “the process”. The audit looks for what wentwell and should be used in the future and what didn’t go well and needsimprovement. Concrete suggestions on how to improve it are encouraged. Theseaudits are done on lectures, student lab sessions and at the end of each quarter.Student feedback is valued and incorporated whenever possible to continuouslyimprove the course.

4. OutreachThe newly developed modules in the microelectronics processing area were implemented in theoutreach programs which are currently in place in the ChE department: (1) Summer Experiencein Science and Engineering for Youth (SESEY), and (2) Saturday Academy and Apprenticeshipsin Science and Engineering (ASE) Program. Each of these programs has a somewhat differentfocus, but share several common underlying themes: exposure of high school students to careersin science and engineering, through research experiences and other opportunities which aretypically not available to them in the high schools; recruitment and retention of underrepresentedgroups (girls and ethnic minorities) into science and engineering; and, a goal of increasing thetechnological literacy of high school students so that they can be empowered to make educatedcareer choices. a Safety analysis tools, such as HAZOP, are also covered in Process Design II (ChE 432). Students must analyzetheir project using at least two methods and include the results of safety analysis in their report.

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The Summer Experience in Science and Engineering for Youth (SESEY): program was initiatedin the summer of 1997 and receives funding from several sources. The primary focus group hasbeen traditionally underrepresented students (females and ethnic minorities) in high school whohave an interest in math and science. The students (approximately 25 per year) are brought to theOregon State University campus for a one-week summer camp where they are paired with afaculty mentor in engineering for a mini-research project. The modules on plasma etching andspin coating has been used twice as mini-research projects. Copper electrodeposition has beenused once. We are in the process of adding new experimental modules to be included in futureyears, providing high school students with a clear view of the applications of chemicalengineering to microelectronics, one of Oregon’s most important industries. SESEY web site:http://www.che.orst.edu/SESEY/

Saturday Academy programs are pre-college, community-based education activities providingextracurricular enriched learning experiences through community professionals. TheApprenticeships in Science and Engineering (ASE) program is part of Saturday Academy and istargeted at the “best and brightest” high school students. The heart of the ASE program is theapprenticeship, in which a student apprentice works with one or more technical professionalmentors for eight weeks full-time during the summer. The OSU ChE Dept. has participated inthe ASE program since 1994. Integration of the microelectronics modules into these summerresearch experiences is an excellent avenue for both recruitment of top rated students intoengineering and exposure of students to technologies relevant to Oregon’s predominant industry.Web site: http://www.ogi.edu/satacad/index.html

5. Assessment PlanThe measurable student outcomes for each unit operations will include the followings:1. The students will demonstrate communication skills.

For example, they will be required to master written and oral reports.2. The students will demonstrate technical synthesis in each of the unit operations. For

example, in CVD, they will use kinetic data in reactor design problems.3. The students will demonstrate professional practices. For example, they will be required to

demonstrate project planning before performing experiments.

Each of these outcomes will be assessed by three methods:1. Student self-assessment and *peer-assessment*, e.g. survey of effectiveness of educational

materials.2. Evaluation of student performance by instructors.3. Feedback from industrial constituency, e.g. survey of student performance from industrial

employer.

6. SummaryThe integration of microelectronics-based unit operations into the ChE curriculum at OSU hasbeen presented. To accomplish this objective, we are developing both lab based and classroombased instruction. Five new unit operations are being implemented in senior lab, including:plasma etching, chemical vapor deposition, spin coating, electrochemical deposition, andchemical mechanical planarization. These labs are also included in an elective, Thin Film

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Materials Processing. Class room examples are being integrated into ChE core engineeringscience classes. By integrating the technical content in this manner, the future process engineersin this industry will be able to draw upon core fundamentals as they go about problem solving.They will also provide breadth to the other students in the class. Simultaneously, the students arelearning professional practices including effective oral and written communications, projectplanning, time management, interpersonal interaction, teamwork, and proactive behavior. Thesemodules are also being used effectively in the SESEY and ASE outreach programs.

7. AcknowledgementsThe authors are grateful for support provided by the Intel Faculty Fellowship Program and theNational Science Foundation’s Course, Curriculum and Laboratory Improvement Program undergrant DUE-0127175. We also acknowledge the Dreyfus Special Grants Program (SG-97-075),OSU precollege programs, Kelley Foundation, Bridges Foundation and NSF (add-on) for theirsupport of the SESEY program and Pete Johnson for the endowment for the Linus PaulingEngineer. SEH America graciously donated the highly polished and oxide coated 6” siliconwafers. Helpful discussions with Emily Allen of San Jose State University and Chuck Croy ofIntel Corporation are greatly appreciated.

8. References

[1] “Initial Placement of Chemical Engineering Graduates,”http://www.aiche.org/careerservices/trends/placement.htm

[2] Microelectronics Processing: Chemical Engineering Aspects, Advanced in Chemistry series, Vol. 221, D.W.Hess and K.F. Jensen eds., American Chemical Society, Washington, DC 1989.

[3] Process Engineering Analysis in Semiconductor Device Fabrication, S. Middleman, McGraw-Hill, New York,NY 1993.

[4] “Thermal Oxidation of Silicon: a Unit Operation for ChEs,” D. W. Hess, S. Bidstrup-Allen, P. Kohl, M. Allenand G. May, presented at Session 19, ASEE Summer School for Chemical Engineering Faculty, Snowbird, UT(1997).

[5] “Interdisciplinary Teaching and Learning in a Semiconductor Processing Course,” A.J.Muscat, E.L. Allen,E.D.H. Green and L.S. Vanasupa, Journal of Engineering Education 87, 413 (1998).

[6] “Fundamentals of Plasma Chemistry,” A.T. Bell, in Techniques and Applications of Plasma Chemistry, A.T.Bell and J.R. Hollahan, Eds., John Wiley & Sons, New York, NY 1974.

[7] “A Continuum Model of DC and rf Discharges,” D. Graves and K.F. Jensen , IEEE Trans. Plasma Sci. P5-14, 78(1986).

[8] “Transient Behavior during Film Removal in Diffusion-Controlled Plasma Etching,” R.C. Alkire and D.J.Economou, J. Electrochem. Soc. 132, 648 (1985).

[9] “A Model of the Chemical Processes Occurring in CF4/O2 Discharges used in Plasma Etching,” I.C. Plumb andK.R. Ryan, Plasma chem. Plasma proc. 6, 231 (1986).

[10] “Modeling and Analysis of Low Pressure CVD Reactors,” K.F. Jensen and D.B. Graves, J. Electrochem. Soc.,130 1950 (1983).

[11] “Low Pressure CVD of Silicon Nitride,” K.F. Roenigk and K.F Jensen, J. Electrochem. Soc., 134(7), 1777-1785(1987).

[12] Elements of Chemical Reaction Engineering, H. Scott Fogler, 3rd Ed., Prentice-Hall PTR 1999. p. 789-795.[13] Automatic Control in Microelectronics Manufacturing:˚ Practices, Challenges, and Possibilities. T.F. Edgar,

S. Butler, W.J. Campbell, C. Pfeiffer, C. Bode, S.B. Hwang, K.S. Balakrishnan and J. Hahn.˚˚Automatica˚ 36,1567 (2000).

[14] “Flow of a Viscous Fluid on a Rotating Disc,” A.G. Emslie, F.T. Bonner and L.G. Peck, Journal of Appl. Phys.29, 858 (1958).

[15] “A Mathematical Model for Spin Coating of Polymer Photoresists,” W.W. Flack, D.S. Soong, A.T. Bell andD.W. Hess, Journal of Appl. Phys. 56, 1199 (1984).

Page 8.753.16

Session 1313


[16] “Spin Coating: One-Dimensional Model,” D.L. Bornside, C.W. Macosko, and L.E. Scriven, Journal of Appl.Phys. 66, 5185 (1989).

[17] “Lubricant Retention on a Spinning Disk,” L. Strong and S. Middleman AIChE J. 35 (10), 1753 (1989).[18] “Some Transport Phenomena Issues in Chemical Mechanical Polishing” R. S. Subramanian and L. Zhang, 3rd

Annual Workshop on Chemical Mechanical Polishing (1998).[19] “Tribology Analysis of Chemical Mechanical Polishing” S. R. Runnels and L. M. Eyman, J. Electrochem. Soc.

141, 1698 (1994).[20] “Investigation of the Kinetics of Tungsten Chemical Mechanical Polishing in Iodate Based Slurries” D. J. Stein,

D. L. Hetherington, and J. L. Cecchi, J. Electrochem. Soc. 146, 376 (1999).[21] “Chemical Mechanical Polishhing Mechanisms of Low Dielectric Constant Polymers in Copper Slurries,” C.l.

Borst, D.G. Thakurta, W.N. Gill, and R.J. Gutmann, J. Electrochem. Soc. 146, 4309 (1999).[22] Chemical Mechanical Planarization of Microelectronic Materials, J. M. Steigerwald, S. P. Murarke, R. J.

Gutman, John Wiley & Sons, New York, NY 1997.[23] “Electrochemical Effects of Various Slurries on the Chemical Mechanical Polishing of Copper-Plated Films”,

Tzu-Hsuan Tsai and Shi-Chern Yen, Submitted to J. Electrochem. Soc.[24] Kepner, Charles H. and Benjamin B. Tregoe, The New Rational Manager, Princeton Research Press, 1981.

Milo D. Koretsky is an Associate Professor of Chemical Engineering at OSU. He received his BS and MS degreesfrom UCSD and Ph D from UC Berkeley, all in chemical engineering. Professor Koretsky’s research interests are inthin film materials processing including: plasma etching, chemical vapor deposition, electrochemical processes andchemical process statistics. His book, Engineering and Chemical Thermodynamics, is due out in December 2003.

Chih-hung (Alex) Chang is an Assistant Professor of Chemical Engineering at OSU. He received his BS degreefrom National Taiwan University and Ph.D. degree from the University of Florida, both in Chemical Engineering.Professor Chang’s research interests include phase equilibria, photovoltaics, X-ray absorption fine structure,electronic materials, nano- and microtechnology.

Sho Kimura is a Professor of Chemical Engineering at OSU. Professor Kimura’s research interests cover high-temperature materials synthesis, nano-sized materials synthesis, surface modifications, applications of high-temperature fluidization technology, reaction kinetics, catalytic effects on gas-solid reactions, and reactor design andsimulations.

Skip Rochefort is an Associate Professor of Chemical Engineering at OSU. He received his BS degree formUMass, his MS degree from Northwestern and Ph D from UCSD, all in chemical engineering. Professor Rocheforthas been recognized for his teaching and advising activities by ASEE, AIChE, and the OSU College of Engineering.His research interests are in all areas of polymer engineering and science, and engineering education.

Cyndie Shaner served as the Linus Pauling Distinguished Engineer at OSU from 2000 to 2002. She received herBS degree form Northwestern University in chemical engineering. Ms. Shaner has 22 years industrial experiencewith Chevron.

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