• Doctoral research performed at the Department of Materials Science and Engineering at the University of Illinois at Urbana-Champaign, in collaboration with chemistry students in Dr. Gregory S. Girolami’s research group • Submitted to Chemistry of Materials for publication, published in doctoral thesis in October 2009 Amount of assumed background knowledge and information: Assumed knowledge areas: Basic chemistry and physics knowledge, chemical nomenclature, ball and stick structures, lability due to spin states, the basics of chemical vapor deposition as a technique, familiarity with a variety of materials characterization techniques and ability to interpret the raw data from them Chemical Vapor Deposition of Manganese Nitride Teresa S. Spicer, PhD, PMP [email protected]http://www.linkedin.com/in/teresaspicer
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
• Doctoral research performed at the Department of Materials Science and Engineering at the University of Illinois at Urbana-Champaign, in collaboration with chemistry students in Dr. Gregory S. Girolami’s research group
• Submitted to Chemistry of Materials for publication, published in doctoral thesis in October 2009
Amount of assumed background knowledge and information:
Assumed knowledge areas: Basic chemistry and physics knowledge, chemical nomenclature, ball and stick structures, lability due to spin states, the basics of chemical vapor deposition as a technique, familiarity with a variety of materials characterization techniques and ability to interpret the raw data from them
Chemical Vapor Deposition of Manganese Nitride
Teresa S. Spicer, PhD, [email protected]://www.linkedin.com/in/teresaspicer
Materials and thin film processing are key to miniaturization
In order to continue miniaturization, thin films of new materials are required.
2007: 30 new materials introduced into 45-nm node1
1 A Thorough Examination of the Electronic Chemicals and Materials Markets, Businesswire, August 15, 2007 Image from http://www.intel.com/pressroom/kits/45nm/photos.htm
❝The implementation of high-k and metal materials marks the biggest change in transistor technology
since the introduction of polysilicon gate MOS transistors in the late
1960s.❞Gordon Moore, Intel Co-Founder, regarding two of the 30
Synthetic inorganic chemistry and materials engineering are required for new CVD processes
Conception and synthesis of new CVD precursor candidates
CVD of films from precursor
Measurement of film properties
Process hypothesis development
Synthesis of modified precursor
Development of novel growth processes and chemistryare needed to develop good CVD processes.
Synthetic inorganic chemistry
Materials engineering
Problem Statement
Tried-and-true concept:
N H
H
H+
Example: Tetrakis(dimethylamido)-titanium(IV) + NH3 → TiN films1-4
1 Dubois, L. H.; Zegarski, B. R.; Girolami, G. S. J. Electrochem. Soc. 1992, 3603–3609. 2 Dubois, L. H. Polyhedron 1994, 13, 1329–1336.
3 Prybyla, J. A.; Chiang, C. M.; Dubois, L. H. J. Electrochem. Soc. 1993, 2695–2702. 4 Fix, R. M.; Gordon, R. G.; Hoffman, D. M. Chem. Mat. 1990, 235–41.
Dialkylamide precursors in particular have worked very well in the past.
Many previous transition metal nitrides have been deposited from amides reacted with ammonia
M NN
RR
R R
Previously, few volatile precursors for Mn-N were known
Due to the size of Mn(II), sterically bulky ligands are required to prevent di- or polymerization of the precursor.
Zinc
30
Zn65.39
Nickel
28
Ni58.693
Cobolt
27
Co58.933
Iron
26
Fe55.845
Scandium
21
Sc44.956
Titanium
22
Ti47.867
Vanadium
23
V50.942
Chromium
24
Cr51.996
Manganese
25
Mn54.938
Copper
29
Cu63.546
Shannon-Prewitt Crystal Ionic Radii of Cations1
Most common oxidation state shown in bold.1
1 Wulfsberg, G. Principles of Descriptive Inorganic Chemistry. University Science Books, Sausalito, CA, 1991.
+388 pm
+2100 pm
+381 pm
+474 pm
+283 pm
+374 pm
+288 pm
+293 pm
+378 pm
+472 pm
+568 pm
+294 pm
+375 pm
+469 pm
+658 pm
+297 pm
+378 pm
+467 pm
+760 pm
+292 pm
+378 pm
+472 pm
+288 pm
+375 pm
+467 pm
+291 pm
+387 pm
Bis[di(tert-butyl)amido]manganese(II) is a monomer and volatile
When reacted with ammonia, bis[di(tert-butyl)amido]Mn(II) should give manganese nitride films.
Spicer, C. W. Synthesis, Characterization and Chemical Vapor Deposition of Transition Metal Di(tert-butyl)amido Compounds. Doctoral dissertation, University of Illinois at Urbana-Champaign: Urbana, IL, 2008.
30% probability surfaces shown.
Experiments
Films were deposited with and without ammonia
Experiment sets:
• Varying T, constant NH3 flow
• Varying NH3 flow, constant T
Substrates:
• Cr-coated Si(100)
Deposition in vacuum chamber➡ In-situ ellipsometer monitors growth➡ Precursor heated to 40 ºC➡ N2 carrier gas
Without NH3
Substrates:
• Si(100)
• α-C TEM grids
Experiment set:
• Varying T
With NH3
N H
H
H
Film phase, composition, roughness, and microstructure data were collected
Auger electron spectroscopy
X-ray diffraction
X-ray photoelectron spectroscopy
* Select films
With NH3 Without NH3
Deposition in vacuum chamber➡ In-situ ellipsometer monitors growth➡ Precursor heated to 40 ºC➡ N2 carrier gas
Transmission electron microscopy* Scanning electron microscopy
Atomic force microscopy
Results
The growth rates are high considering the low growth temperatures
The reaction between bis[di(tert-butyl)]amidoMn(II) and ammonia is very facile.
Dr. Mauro Sardela, UIUCNancy Finnegan, UIUC (Ret.)
Dr. Tim Spila, UIUCDr. Richard Haasch, UIUC
Subhash Gujrathi, Université de Montreal
Research supported by NSF grant DMR-0420768
Film characterization was carried out in the Center for Microanalysis of Materials, University of Illinois, which is partially supported by the U.S. Department of