Microsecond carrier lifetimes in strained silicon‐germanium alloys grown by rapid thermal chemical vapor deposition

1990 ◽  
Vol 57 (19) ◽  
pp. 2004-2006 ◽  
Author(s):  
P. V. Schwartz ◽  
J. C. Sturm
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Silicon Germanium ◽  
Chemical Vapor ◽  
Strained Silicon ◽  
Thermal Chemical Vapor Deposition ◽  
Carrier Lifetimes ◽  
Silicon Germanium Alloys

Rapid Thermal Chemical Vapor Deposition of Polycrystalline Silicon-Germanium Films on SiO2 and Their Properties

1995 ◽  
Vol 403 ◽  
Author(s):  
V. Z-Q Li ◽  
M. R. Mirabedini ◽  
R. T. Kuehn ◽  
D. Gladden ◽  
D. Batchelor ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Silicon Germanium ◽  
Deposition Temperature ◽  
Chemical Vapor ◽  
Grain Structure ◽  
Germanium Content ◽  
Thermal Chemical Vapor Deposition ◽  
Nucleation Sites

AbstractIn this work, polycrystalline SiGe has been viewed as an alternative gate material to polysilicon in single wafer processing for the deep submicrometer VLSI applications. We studied deposition of the silicon-germanium (SiGe) films with different germanium concentrations (up to 85%) on SiO2 in a rapid thermal chemical vapor deposition reactor using GeH4 and SiH4/H2 gas mixture with the temperature ranging from 550°C to 625°C. Since the SiGe RTCVD process is selective toward oxide and does not form nucleation sites on the oxide easily, an in-situ polysilicon flash technique is used to provide the necessary nucleation sites for the deposition of SiGe films with high germanium content. It was observed that with the in-situ polysilicon flash as a pre-nucleation seed, the SiGe deposited on SiO2 forms a continuous polycrystalline layer. Polycrystalline SiGe films of about 2000Å in thickness have a columnar grain structure with a grain size of approximately 1000Å. Compositional analyses from Auger Electron Spectroscopy (AES) and Rutherford backscattering (RBS) show that the high germanium incorporation in the SiGe films has a weak dependence on the deposition temperature. It is also noted that the germanium content across the film thickness is fairly constant which is a critical factor for the application of SiGe films as the gate material. Lastly, we found that the surface morphology of SiGe films become smoother at lower deposition temperature.

Well-Resolved Band-Edge Photoluminescence from Strained Si1–xGex Layers Grown by Rapid Thermal Chemical Vapor Deposition

1991 ◽  
Vol 220 ◽  
Author(s):  
J. C. Sturm ◽  
P. V. Schwartz ◽  
H. Manoharan ◽  
Q. Mi ◽  
L. C. Lenchyshyn ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Quantum Wells ◽  
Vapor Deposition ◽  
Silicon Germanium ◽  
Chemical Vapor ◽  
Band Edge ◽  
Strained Layers ◽  
Alloy Scattering ◽  
Thermal Chemical Vapor Deposition ◽  
Band Edge Luminescence

ABSTRACTWell resolved band-edge luminescence of excitons in silicon-germanium alloy strained layers, quantum wells, and superlattices has been observed in films grown by Rapid Thermal Chemical Vapor Deposition. The signal is due to bound excitons at low temperatures and free excitons at higher temperatures, and has a strong no-phonon signal which is caused by alloy scattering. Bandgaps inferred from photoluminescence agree well with those measured by absorption spectroscopy, inferring that a no-phonon process dominates the band-edge absorption.

Selective Deposition of Silicon and Silicon-Germanium Alloys by Rapid Thermal Chemical Vapor Deposition

1996 ◽  
Vol 429 ◽  
Author(s):  
John M. Grant ◽  
Ming Ang ◽  
Lynn R. Allen
Keyword(s):  
Surface Roughness ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Silicon Germanium ◽  
Chemical Vapor ◽  
Native Oxide ◽  
Initiation Time ◽  
Selective Deposition ◽  
Thermal Chemical Vapor Deposition ◽  
Oxide Removal

AbstractSelective deposition of SiGe alloys by rapid thermal deposition has been studied using a commercially available Rapid Thermal Chemical Vapor Deposition (RTCVD) cluster tool. The precursors used in this work were dichlorosilane and germane diluted in either hydrogen or argon. An initial characterization was performed to find the appropriate temperature and GeH4 flow ranges to deposit epitaxial layers with low surface roughness. For layers with higher germanium concentration lower deposition temperatures are required to minimize surface roughness. The effects of the dilutant gas on the deposition were examined. An H2 dilutant affects the deposition by consuming chlorine released by the SiCl2H2 and forming HCI. When Ar is used as the dilutant, more chlorine is available for other reactions that can result in etching of the silicon surface. Finally, the effects of pre-deposition treatment were determined. When compared to a wet HF dip, a gas/vapor phase HF/methanol native oxide removal treatment appears to increase the initiation time for the epitaxial deposition reaction. This is most likely due to increased fluorine termination of the surface. When a wet HF or HF/methanol native oxide removal is followed by a UV-Cl2 process, the deposition reaction initiation time is reduced. The UV-Cl2 process was also found to etch silicon through the native oxide.

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