Excimer Laser Induced Crystallization of Amorphous Silicon-Germanium Films

1993 ◽  
Vol 321 ◽  
Author(s):  
A. Slaoui ◽  
C. Deng ◽  
S. Talwar ◽  
J. K. Kramer ◽  
B. Prevot ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Excimer Laser ◽  
Silicon Germanium ◽  
Laser Energy ◽  
Electron Gun ◽  
Laser Crystallization ◽  
Time Resolved ◽  
Si Substrates ◽  
Si Films ◽  
Amorphous Silicon Germanium

ABSTRACTApplication of excimer laser crystallization of Amorphous silicon (a-Si) has introduced a new, interesting potential technology for the fabrication of polycrystalline (poly-Si) thin film transistors. We are currently studying polycrystalline Si1−xGex thin films in order to determine whether this material can lead to improved electrical properties or to better processing requirements when compared with polycrystalline Si films. In this work we analyze by RBS, TEM, Raman spectroscopy and surface reflectance, the structure of thin Amorphous Si1−xGex films after irradiation with a XeCl excimer laser. The Amorphous SiGe films were prepared by evaporation of Si and Ge onto oxidized Si substrates using an electron gun in vaccum. The effects of laser energy fluence during irradiation are investigated. The Amorphous to crystalline transition is followed by in-situ measurement of time-resolved reflectivity.

Free Carrier Lifetime in a-Si,Ge:H Alloys

1992 ◽  
Vol 258 ◽  
Author(s):  
D.A. Young ◽  
P.M. Fauchek ◽  
Y.M. Liu ◽  
W.L. Nighan ◽  
C.M. Fortmann
Keyword(s):  
Amorphous Silicon ◽  
Time Domain ◽  
Silicon Germanium ◽  
Free Electron Laser ◽  
Carrier Lifetime ◽  
Free Carrier ◽  
Time Resolved ◽  
Pump And Probe ◽  
Extended States ◽  
Amorphous Silicon Germanium

ABSTRACTThe lifetime of carriers injected optically in the extended states of amorphous silicon-germanium alloys has been measured by time-resolved pump and probe optical techniques using either a femtosecond dye laser or a picosecond free electron laser. When Ninj > 1018 cm-3, the lifetime of the carriers is in the picosecond time domain. Our results are comparable to what we have observed previously in a-Si:H and very recently in a-Si,C:H. There are two lifetime regimes: at high densities, the recombination is bimolecular and nonradiative, whereas at lower densities, the recombination tends to be monomolecular but still nonradiative. The origin of these lifetimes is discussed.

Metastable Defects in the Amorphous Silicon-Germanium Alloys

2003 ◽  
Vol 762 ◽  
Author(s):  
J. David Cohen
Keyword(s):  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Dangling Bonds ◽  
Annealing Behavior ◽  
Fundamental Properties ◽  
Silicon Materials ◽  
Salient Features ◽  
The Individual ◽  
Amorphous Silicon Germanium ◽  
Silicon Germanium Alloys

AbstractThis paper first briefly reviews a few of the early studies that established some of the salient features of light-induced degradation in a-Si,Ge:H. In particular, I discuss the fact that both Si and Ge metastable dangling bonds are involved. I then review some of the recent studies carried out by members of my laboratory concerning the details of degradation in the low Ge fraction alloys utilizing the modulated photocurrent method to monitor the individual changes in the Si and Ge deep defects. By relating the metastable creation and annealing behavior of these two types of defects, new insights into the fundamental properties of metastable defects have been obtained for amorphous silicon materials in general. I will conclude with a brief discussion of the microscopic mechanisms that may be responsible.

Properties of Catalytic-Cvd Amorphous Silicon-Germanium (a-SiGe:H)

1990 ◽  
Vol 192 ◽  
Author(s):  
Hideki Matsumura ◽  
Masaaki Yamaguchi ◽  
Kazuo Morigaki
Keyword(s):  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Hydrogenated Amorphous Silicon ◽  
Chemical Vapor ◽  
Characteristic Energy ◽  
Optical Band Gaps ◽  
Spin Resonance ◽  
Amorphous Silicon Germanium ◽  
Conductive Properties ◽  
Hydrogenated Amorphous

ABSTRACTHydrogenated amorphous silicon-germanium (a-SiGe:H) films are prepared by the catalytic chemical vapor deposition (Cat-CVD) method using a SiH4, GeH4 and H4 gas mixture. Properties of the films are investigated by the photo-thermal deflection spectroscopy (PDS) and electron spin resonance (ESR) measurements, in addition to the photo-conductive and structural studies. It is found that the characteristic energy of Urbach tail, ESR spin density and other photo-conductive properties of Cat-CVD a-SiGe:H films with optical band gaps around 1.45 eV are almost equivalent to those of the device quality glow discharge hydrogenated amorphous silicon (a-Si:H).

Medium-Range Order of Amorphous Silicon Germanium Alloys: Small-Angle X-Ray Scattering Study

1989 ◽  
Vol 28 (Part 2, No. 7) ◽  
pp. L1092-L1095 ◽  
Author(s):  
Shin-ichi Muramatsu ◽  
Toshikazu Shimada ◽  
Hiroshi Kajiyama ◽  
Kazufumi Azuma ◽  
Takeshi Watanabe ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Small Angle ◽  
Silicon Germanium ◽  
Range Order ◽  
Medium Range Order ◽  
X Ray ◽  
X Ray Scattering ◽  
Medium Range ◽  
Scattering Study ◽  
Amorphous Silicon Germanium

Amorphous silicon-germanium alloy multilayers for solar cells

1988 ◽  
Author(s):  
J.P. Conde ◽  
V. Chu ◽  
S. Tanaka ◽  
D.S. Shen ◽  
S. Wagner
Keyword(s):  
Solar Cells ◽  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Germanium Alloy ◽  
Amorphous Silicon Germanium
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