Amorphous silicon-germanium (a-Si0.01Ge0.99:H) doped with phosphorous deposited by LF PECVD and its electrical and optical characteristics

2012 ◽  
Vol 1426 ◽  
pp. 409-414
Author(s):  
N. Delgadillo ◽  
A. Kosarev ◽  
A. Torres ◽  
B. Gonzales
Keyword(s):  
Activation Energy ◽  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Solid Phase ◽  
Low Frequency ◽  
Localized State ◽  
Temperature Dependence Of Conductivity ◽  
P Content ◽  
Amorphous Silicon Germanium ◽  
Preferential Incorporation

ABSTRACTAmorphous silicon-germanium (a-Si0.01Ge0.99:H) thin film, practically amorphous germanium with small concentration of silicon, were deposited by the low frequency PECVD technique under different flow gas of phosphine in the range of QPH3 = 20 to 100 sccm. In this range the phosphorous concentration in gas phase was calculated as XP= 4 to 20 % which resulted in a content in solid phase [P]sol=0.12% - 0.4%. The P content of the solid phase was measured by SIMS profiling and it was also observed a preferential incorporation of phosphorous in the range of [P]sol=0.12% - 0.3%. Hydrogen concentration in the films was determined from FTIR and SIMS measurements. The activation energy was determined by measuring the temperature dependence of conductivity in DC regime in a vacuum thermostat. For the a-Si0.01Ge0.99:H films it is found that the activation energy have a minimum, (Ea= 0.15eV), its conductivity at room temperature have a maximum and there is a minimum of of both band tail and deep localized state for a phosphorous incorporation in solid phase [P] =0.28%.

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.

The Electrical Characterization of Hydrogenated Amorphous Silicon Germanium Film Used in Un-Cooled Micro-Bolometer

2018 ◽  
Vol 937 ◽  
pp. 3-8
Author(s):  
Zhe Quan Chen ◽  
He Yong ◽  
Zhong Fang ◽  
Xu Chao Phan ◽  
He Yuan
Keyword(s):  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Hydrogenated Amorphous Silicon ◽  
Chemical Vapour ◽  
Electrical Characterization ◽  
Deposition Parameter ◽  
Temperature Dependence Of Conductivity ◽  
Amorphous Silicon Germanium ◽  
Hydrogenated Amorphous

In this paper, the deposition and the electrical characterization of hydrogenated amorphous silicon germanium (a-SixGey:H) thin films were performed by plasma enhanced chemical vapour deposition (PECVD) at low temperature with different flow ratios of SiH4/GeH4. The temperature coefficient of resistance (TCR) and temperature dependence of conductivity were measured to study the influence of deposition parameter. The resistance uniformity were also investigated. The result showed that the film presented high TCR values of around 3.5%K-1and moderate conductivity value of 1.47×10-3(Ω•cm)-1respectively at room temperature, while the non-uniformity below 5% which indicated the high resistance uniformity in films.

Amorphous Si1-YGeY:H, F films obtained by Low Frequency PECVD for uncooled microbolometers

2004 ◽  
Vol 808 ◽  
Author(s):  
R. Ambrosio ◽  
A. Torres ◽  
A. Kosarev ◽  
A. S. Abramov ◽  
A. Heredia ◽  
...  
Keyword(s):  
Activation Energy ◽  
Room Temperature ◽  
Solid Phase ◽  
Low Frequency ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
Sensing Material ◽  
Temperature Dependence Of Conductivity ◽  
Ir Transmission ◽  
High Absorption

ABSTRACTIn this work, we report the composition, optical, and electrical properties of a- Si1-YGeY: H, F films to be used as sensing layer in uncooled microbolometers. The a-Si1-YGeY films where Y is Ge content in solid phase were deposited by low frequency PECVD from SiH4 and GeF4 feed gases, and H2 and Ar were used for dilution. The film composition, IR transmission and temperature dependence of conductivity were measured. The reduction of conductivity activation energy from 0.86 eV to 0.39 eV and the increase of room temperature conductivity from 1x10−9 to 2.1×10−3 Ohm−1cm−1 were observed with the change of Y from 0 (Si) to 1(Ge). These results demonstrate this material to be a good candidate as a sensing material in uncooled micro-bolometers, due to its high absorption in the range of λ = 10-13 μm, its relatively high activation energy, Ea=0.4 eV, consequently, a high temperature coefficient of resistance (TCR), and moderate resistivity at room temperature.

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
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