Low Resistivity Boron Doped Amorphous Silicon-Germanium Alloy Films Obtained with a Low Frequency

2003 ◽  
Vol 796 ◽  
Author(s):  
Plasma A. Heredia-J ◽  
A. Torres-J ◽  
F.J. De la Hidalga-W ◽  
A. Jaramillo-N ◽  
J. Sanchez-M ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Low Frequency ◽  
Chemical Vapor ◽  
Refraction Index ◽  
Alloy Films ◽  
Boron Doped ◽  
Structural And Electrical Properties ◽  
Germanium Alloy ◽  
Amorphous Silicon Germanium

AbstractThe structural and electrical properties of boron doped amorphous silicon-germanium alloy films, obtained using a low frequency plasma enhanced chemical vapor deposition (LF PECVD), are presented in this contribution. These thin films were deposited on a substrate heated at 270°C, and by decomposing a mixture of silane, germane, and diborane gases. The chemical bond structure was studied by Infrared Spectroscopy. Our results show that, for a constant diborane flow, the increase of germane flow enhances the incorporation of boron into the film; the peak at 2540 cm−1 becomes larger as the Ge content increases. Transport of carriers was studied by measuring current-voltage curves as a function of temperature. The conductivity increased from 10−6 to 10 (Ω-cm)−1, while the refraction index increased from 3.312 to 4.4458, for an increasing Ge content; this makes the films suitable for optical waveguide applications. On the other hand, the activation energy varied from 0.668 to 0.220 eV when the sample was doped with boron. The AFM images showed that the surface roughness was improved for an alloy with 50% of Ge.

A Novel Amorphous SiGe Material Used in CMOS Device

2011 ◽  
Vol 291-294 ◽  
pp. 465-468
Author(s):  
Wei Cui ◽  
Shi Lu Xu ◽  
Ping Li ◽  
Ting Ma ◽  
Yong Hui Yang
Keyword(s):  
Low Temperature ◽  
Amorphous Silicon ◽  
Breakdown Voltage ◽  
Silicon Germanium ◽  
Minority Carrier ◽  
Low Frequency ◽  
Current Gain ◽  
Germanium Alloy ◽  
Novel Material ◽  
Amorphous Silicon Germanium

In this paper, we propose a novel material- amorphous silicon germanium(a-SiGe). The a-SiGe film was formed by PECVD at a low temperature and a low frequency. By adjusting the fraction x of Ge in Si1-xGex, optimal SiGe bandgap was achieved. We used amorphous silicon germanium alloy as MOSFET source/drain. The parameter of MOSFET shows that, as the fraction increases, the drain-to-source breakdown voltage increases. With reduction of the minority carrier inject ratio, the current gain β of parasitic BJT in MOSFET was reduced greatly, which eliminates the limit of the breakdown voltage of the device.

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).

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

scholarly journals Amorphous Silicon-Germanium Films with Embedded Nanocrystals for Thermal Detectors with Very High Sensitivity

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Cesar Calleja ◽  
Alfonso Torres ◽  
Pedro Rosales-Quintero ◽  
Mario Moreno
Keyword(s):  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Chemical Vapor ◽  
Focal Plane Arrays ◽  
Large Temperature ◽  
Thermal Coefficient ◽  
Thermal Detectors ◽  
Germanium Films ◽  
Amorphous Silicon Germanium ◽  
Very High

We have optimized the deposition conditions of amorphous silicon-germanium films with embedded nanocrystals in a plasma enhanced chemical vapor deposition (PECVD) reactor, working at a standard frequency of 13.56 MHz. The objective was to produce films with very large Temperature Coefficient of Resistance (TCR), which is a signature of the sensitivity in thermal detectors (microbolometers). Morphological, electrical, and optical characterization were performed in the films, and we found optimal conditions for obtaining films with very high values of thermal coefficient of resistance (TCR = 7.9% K−1). Our results show that amorphous silicon-germanium films with embedded nanocrystals can be used as thermosensitive films in high performance infrared focal plane arrays (IRFPAs) used in commercial thermal cameras.

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