Post on 13-Dec-2015
Basic OverviewBasic Overview Kinetically Controlled Vapor Diffusion Kinetically Controlled Vapor Diffusion
Synthesis Of Chromium Doped Synthesis Of Chromium Doped Indium Hydroxide Thin FilmsIndium Hydroxide Thin Films
Faculty Advisor:Faculty Advisor: Dr. Dan MorseDr. Dan Morse
Research Mentors: Research Mentors: Dr. Birgit Schwenzer, James NeilsonDr. Birgit Schwenzer, James Neilson
RET Advisor: RET Advisor: Dr. Martina MichenfelderDr. Martina Michenfelder
RET Participant: RET Participant: Jason SmithJason Smith
RET research funding made possible by the National Science Foundation RET research funding made possible by the National Science Foundation (NSF)(NSF)
Morse Group Funding: The Defense Advanced Research Projects Morse Group Funding: The Defense Advanced Research Projects Agency (DARPA) and The Department of Energy (DOE)Agency (DARPA) and The Department of Energy (DOE)
PurposePurpose
To create stable, To create stable, crystalline films of indium crystalline films of indium oxide oxide
To attain “tunable levels ” To attain “tunable levels ” of chromium dopingof chromium doping
Basic researchBasic research
T.Tomita, K.Yamashita and J.Yasui and Y.Hayafuji, “Electronic Structures of Indium Oxide with Point Defects” and Bull.Soc.Discrete Variational Xα, 16, O-2p09 (2003) (in press).
Potential ApplicationsPotential Applicationsbeyond basic researchbeyond basic research
Memory devices and spin valves Memory devices and spin valves in the new frontier of in the new frontier of “spintronics”“spintronics”
SemiconductorsSemiconductors MultiferroicsMultiferroics The unknown . . The unknown . .
What is a chromium doped indium What is a chromium doped indium hydroxide thin film?hydroxide thin film?
It is just that. A thin film It is just that. A thin film (thickness not yet determined )(thickness not yet determined )
Forms on surface of aqueous Forms on surface of aqueous solution given proper solution given proper precursors and catalysts.precursors and catalysts.
Somewhat resembles a lily leaf Somewhat resembles a lily leaf (no scientific relevance) in (no scientific relevance) in shape, color and location* shape, color and location*
( *floating on aqueous ( *floating on aqueous solution). solution).
DopingDoping Film framework (base Film framework (base
material) is indium material) is indium hydroxide hydroxide
Doping = substitutionDoping = substitutionchromium is substituted for chromium is substituted for indium (see schematic)indium (see schematic)
May result in unique May result in unique electrical and magnetic electrical and magnetic propertiesproperties
Annealing (heating) film may Annealing (heating) film may result in crystalline structure result in crystalline structure of indium oxide doped with of indium oxide doped with chromium, the desired resultchromium, the desired result
Un-doped indium hydroxide
Doped
DopingDoping
A brief animationA brief animation
LingoLingo
X-ray diffractionX-ray diffraction XRDXRD
Scanning electron microscopyScanning electron microscopy SEM SEM
Energy dispersive spectroscopyEnergy dispersive spectroscopy EDS EDS
Inductively coupled plasma spectroscopyInductively coupled plasma spectroscopy ICPICP
Carbon, hydrogen, nitrogen, analysis Carbon, hydrogen, nitrogen, analysis CHNCHN
Indium nitrate hydrate Indium nitrate hydrate In(NOIn(NO33))33·XH·XH22OO
Chromium III nitrate Chromium III nitrate Cr(NOCr(NO33) ) 33
Ammonium hydroxideAmmonium hydroxide NHNH44OHOH
Materials and MethodsMaterials and MethodsGeneral OverviewGeneral Overview
indium nitrate hydrate, indium nitrate hydrate, and the dopant and the dopant chromium III nitrate, are chromium III nitrate, are added to top and bottom added to top and bottom rows of wells of 12 well rows of wells of 12 well reaction plate (noted IC)reaction plate (noted IC)
Well plate placed in covered reaction box,over several hoursthin films form
Remove films from wells, whole films are “washed”, “powders” are filtered
Whole films analyzed by SEM/EDS for structure,elemental composition and % chromiumincorporation
Powders/ filmfragmentsanalyzed by XRD forcrystallinity
CHN analysis ICP analysis
solution of ammonium solution of ammonium hydroxide (noted N), hydroxide (noted N), is added to middle wells
Materials and MethodsMaterials and Methods
A 2A 2ndnd brief animation brief animation
X-ray diffraction of X-ray diffraction of thin film thin film
nanoparticles with nanoparticles with varying Cr doping varying Cr doping
levelslevels
• XRD: Utilized as a method for determining crystallinity
• Peak at (22°[2Ө]) corresponding to d spacing of 4.04 Å, indium hydroxide’s most intensely scattering lattice plane
• sharp peak indicates crystallinity, higher doping (10%) results in amorphous background signal no sharp crystalline peak
10%
8%
6%
4%
2%
0%
EDS Data OverviewEDS Data Overview
In Conjunction With Qualitative In Conjunction With Qualitative DataData
• Low doping ( 2-4%) : macroscopically thin, brittle, films, predictable doping
• High doping ( 10%) : macroscopically thick, stable films, unpredictable doping
• 6% Cr doping: consistent film stability and dopant incorporation, averaged 5.17 at% (twelve experiments, forty-four data sets), candidate for further analysis
Chromium doping incorporation in indium hydroxide thin films at varying doping levels
0
2
4
6
8
10
12
14
0 2 4 6 8 10 12
Theoretical Cr Incorporation
Ac
tua
l C
r In
co
rpo
rati
on
Series1
Lessons LearnedLessons Learned
I learned that a thorough I learned that a thorough understanding only understanding only comes with thorough comes with thorough and complete analysis and complete analysis
I learned the importance I learned the importance of accuracy and of accuracy and attention to detailattention to detail
I learned that patience is I learned that patience is a virtue necessary for a virtue necessary for
basic researchbasic research Peer reviews can be Peer reviews can be
painful but enlighteningpainful but enlightening
Special Thank YouSpecial Thank You
To Dr. Martina Michenfelder for her endless patience To Dr. Martina Michenfelder for her endless patience and wisdomand wisdom
To the staff of the MRL for making and creating such To the staff of the MRL for making and creating such an outstanding opportunity for teachersan outstanding opportunity for teachers
To the NSF for continuing its dedication to support To the NSF for continuing its dedication to support science and explorationscience and exploration
To the Morse Group for a glimpse into biomimetic To the Morse Group for a glimpse into biomimetic chemistrychemistry
Preliminary ConclusionPreliminary Conclusion
Indium hydroxide thin film Indium hydroxide thin film chromium doping/chromium doping/
incorporation can be incorporation can be influenced by adjusting influenced by adjusting chromium levels of starting chromium levels of starting solutionsolution
ResourcesResources
Indium oxide structure Indium oxide structure
(image 1) (image 1)
T.Tomita, T.Tomita, K.YamashitaK.Yamashita and J.Yasui and J.Yasui and Y.Hayafuji, “Electronic Structures and Y.Hayafuji, “Electronic Structures of Indium Oxide with Point Defects” of Indium Oxide with Point Defects” and Bull.Soc.Discrete Variational Xα, and Bull.Soc.Discrete Variational Xα, 1616, O-2p09 (2003) (in press)., O-2p09 (2003) (in press).
Lily image courtesy of Lily image courtesy of http://www.pirateplanet.com/http://www.pirateplanet.com/