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Title: Chemical routes to Ge/Si(100) structures for low temperature Si-based semiconductor applications

Abstract

The authors describe very low temperature (350-420 deg. C) growth of atomically smooth Ge films (0.2-0.4 nm roughness) directly on Si(100) via gas-source molecular beam epitaxy. A carefully tuned admixture of (GeH{sub 3}){sub 2}CH{sub 2}, possessing unique pseudosurfactant properties, and conventional Ge{sub 2}H{sub 6} provides unprecedented control of film microstructure, morphology, and composition. Formation of edge dislocations at the interface ensures growth of virtually relaxed monocrystalline Ge films ({approx}40-1000 nm thick) with a threading dislocation density less than 10{sup 5} cm{sup -2} as determined by etch pit measurements. Secondary ion mass spectroscopy showed no measurable carbon incorporation indicating that C desorbs as CH{sub 4}, consistent with calculated chemisorption energies.

Authors:
; ; ; ;  [1]
  1. Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287 (United States)
Publication Date:
OSTI Identifier:
20971845
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 8; Other Information: DOI: 10.1063/1.2437098; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARBON; CHEMISORPTION; CRYSTAL GROWTH; DESORPTION; EDGE DISLOCATIONS; GERMANIUM; GERMANIUM HYDRIDES; ION MICROPROBE ANALYSIS; MASS SPECTRA; MASS SPECTROSCOPY; METHANE; MICROSTRUCTURE; MOLECULAR BEAM EPITAXY; MORPHOLOGY; ROUGHNESS; SEMICONDUCTOR MATERIALS; SILICON; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0400-1000 K; THIN FILMS

Citation Formats

Wistey, M. A., Fang, Y.-Y., Tolle, J., Chizmeshya, A. V. G., and Kouvetakis, J.. Chemical routes to Ge/Si(100) structures for low temperature Si-based semiconductor applications. United States: N. p., 2007. Web. doi:10.1063/1.2437098.
Wistey, M. A., Fang, Y.-Y., Tolle, J., Chizmeshya, A. V. G., & Kouvetakis, J.. Chemical routes to Ge/Si(100) structures for low temperature Si-based semiconductor applications. United States. doi:10.1063/1.2437098.
Wistey, M. A., Fang, Y.-Y., Tolle, J., Chizmeshya, A. V. G., and Kouvetakis, J.. Mon . "Chemical routes to Ge/Si(100) structures for low temperature Si-based semiconductor applications". United States. doi:10.1063/1.2437098.
@article{osti_20971845,
title = {Chemical routes to Ge/Si(100) structures for low temperature Si-based semiconductor applications},
author = {Wistey, M. A. and Fang, Y.-Y. and Tolle, J. and Chizmeshya, A. V. G. and Kouvetakis, J.},
abstractNote = {The authors describe very low temperature (350-420 deg. C) growth of atomically smooth Ge films (0.2-0.4 nm roughness) directly on Si(100) via gas-source molecular beam epitaxy. A carefully tuned admixture of (GeH{sub 3}){sub 2}CH{sub 2}, possessing unique pseudosurfactant properties, and conventional Ge{sub 2}H{sub 6} provides unprecedented control of film microstructure, morphology, and composition. Formation of edge dislocations at the interface ensures growth of virtually relaxed monocrystalline Ge films ({approx}40-1000 nm thick) with a threading dislocation density less than 10{sup 5} cm{sup -2} as determined by etch pit measurements. Secondary ion mass spectroscopy showed no measurable carbon incorporation indicating that C desorbs as CH{sub 4}, consistent with calculated chemisorption energies.},
doi = {10.1063/1.2437098},
journal = {Applied Physics Letters},
number = 8,
volume = 90,
place = {United States},
year = {Mon Feb 19 00:00:00 EST 2007},
month = {Mon Feb 19 00:00:00 EST 2007}
}
  • We report the properties of silicon nitride films deposited by the electron cyclotron resonance remote plasma enhanced chemical vapor deposition method on Si substrates using SiH{sub 4} and N{sub 2}. The effects of nitrogen/silane gas ratio ({ital R}=N{sub 2}/SiH{sub 4}), electron cyclotron resonance power, substrate temperature, and H on growth, refractive index, chemical composition, and etch rate were investigated. Nominally stoichiometric Si{sub 3}N{sub 4} films were obtained with a refractive index of 1.9{approximately}2.0 at a wavelength of 632.8 nm. The etch rate of the films in a buffered HF solution (7:1) was low ({approximately}0.7 nm/min) and increased with increasing H{submore » 2} gas flow rate and decreasing substrate temperature during deposition. Fourier transform infrared spectroscopy and high temperature thermal evolution experiments showed very small amounts of H in the films. A leakage current less than 100 pA/cm{sup 2} at a field of 2 MV/cm, a resistivity of {approx_gt}4{times}10{sup 17} {Omega}cm, and breakdown strengths of 6{endash}11 MV/cm at a current density of 1 {mu}A/cm{sup 2} were observed. These properties are comparable to those of Si{sub 3}N{sub 4} prepared by conventional high temperature (700{degree}C) chemical vapor deposition. The performance of GaAs-based field-effect-transistors in switching and power applications can be enhanced substantially by employing a metal-insulator-semiconductor structure. By taking advantage of an {ital in} {ital situ} process approach, insulator-GaAs structures were successfully gated with excellent interfacial properties. {copyright} {ital 1996 American Vacuum Society}« less
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