High Rate Deposition of a-SiNxH by VHF PECVD

1997 ◽  
Vol 467 ◽  
Author(s):  
T. Takagi ◽  
Y. Nakagawa ◽  
Y. Watabe ◽  
K. Takechi ◽  
S. Nishida
Keyword(s):  
Amorphous Silicon ◽  
Deposition Rate ◽  
Excitation Frequency ◽  
Chemical Vapour ◽  
Optical Emission ◽  
High Rate ◽  
Very High Frequency ◽  
Silicon Nitride Films ◽  
Very High

ABSTRACTVery High Frequency (VHF) has been applied to the plasma enhanced chemical vapour deposition (PECVD) of hydrogenated amorphous silicon nitride films (a-SiNx:H) to fabricate amorphous silicon (a-Si:H) thin film transistors (TFTs). Especially, the effect of the excitation frequency on the deposition rate and the film quality of a-SiNx.H deposited in a SiH4/NH3/N2 plasma has been investigated. The films were prepared by VHF (40 MHz and 60 MHz) and HF (13.56 MHz) plasma enhanced CVD.The optical bandgap, the hydrogen content, the Si-H/N-H ratio and TFT mobility for films deposited in VHF plasma did not change significantly with the increase in deposition rate up to 300 nm/min. Internal stress could be constrained to acceptable levels at very high deposition rates. In contrast, the film quality deteriorated with an increase of the deposition rate in HF plasma. There seems to be a parallel relation between the optical emission intensity and the deposition rate which depends on the excitation frequency.

Large Grain Size and High Deposition Rate for Microcrystalline Silicon Prepared by VHF-GD

1994 ◽  
Vol 358 ◽  
Author(s):  
P. Hapke ◽  
F. Finger ◽  
M. Luysberg ◽  
R. Carius ◽  
H. Wagner
Keyword(s):  
Grain Size ◽  
Deposition Rate ◽  
High Frequency ◽  
Excitation Frequency ◽  
Chemical Vapour ◽  
High Deposition Rate ◽  
Very High Frequency ◽  
Deposition Parameters ◽  
Plasma Excitation ◽  
Very High

ABSTRACTThe growth mechanism and material properties of -type µc-Si:H prepared with plasma enhanced chemical vapour deposition in the very high frequency range is investigated. By increasing the plasma excitation frequency the grain size, deposition rate and Hall mobility can be simultaneously increased without having to adjust other deposition parameters in particular the temperature. This effect is explained by an enhanced selective etching of amorphous tissue and grain boundary regions together with a sufficient supply of growth species at high frequency plasmas.

High-Rate Deposition of Intrinsic Amorphous Silicon Layers for Solar Cells using Very High Frequency Plasma at Atmospheric Pressure

2005 ◽  
Author(s):  
Hiroaki Kakiuchi ◽  
Hiromasa Ohmi ◽  
Yasuhito Kuwahara ◽  
Mitsuhiro Matsumoto ◽  
Yusuke Ebata ◽  
...  
Keyword(s):  
Solar Cells ◽  
Amorphous Silicon ◽  
Atmospheric Pressure ◽  
High Frequency ◽  
High Rate ◽  
Very High Frequency ◽  
High Frequency Plasma ◽  
Frequency Plasma ◽  
Very High

Versatile High Rate Plasma Deposition and Processing with very high Frequency Excitation

1997 ◽  
Vol 467 ◽  
Author(s):  
M. Heintze
Keyword(s):  
Growth Rates ◽  
High Frequency ◽  
Plasma Deposition ◽  
Excitation Frequency ◽  
High Growth ◽  
Surface Reactivity ◽  
High Rate ◽  
Plasma Diagnostic ◽  
Very High Frequency ◽  
Very High

ABSTRACTThe interest in plasma deposition using very high frequency (VHF) excitation arose after the preparation of a-Si:H at high growth rates was demonstrated. Subsequently the improved process flexibility and the control of material properties offered by the variation of the plasma excitation frequency was recognized. The preparation of amorphous and microcrystalline thin films in a VHF-plasma is described. The increased growth rates have been attributed to an enhancement of film precursor formation at VHF, to the decreased sheath thickness as well as to an enhancement of the surface reactivity by positive ions. Plasma diagnostic investigations show that the parameters mainly affected by the excitation frequency are the ion flux to the electrodes as well as the sheaths potentials and widths, rather than the plasma density.

High Rate Deposition of Amorphous Silicon Based Solar Cells using Modified Very High Frequency Glow Discharge

2007 ◽  
Vol 989 ◽  
Author(s):  
Guozhen Yue ◽  
Baojie Yan ◽  
Jeffrey Yang ◽  
Subhendu Guha
Keyword(s):  
Solar Cells ◽  
Glow Discharge ◽  
Amorphous Silicon ◽  
High Frequency ◽  
Cell Performance ◽  
High Rate ◽  
Active Area ◽  
Very High Frequency ◽  
Single Junction ◽  
Very High

AbstractWe report our recent progress on high rate deposition of hydrogenated amorphous silicon (a-Si:H) and silicon germanium (a-SiGe:H) based n-i-p solar cells. The intrinsic a-Si:H and a-SiGe:H layers were deposited using modified very high frequency (MVHF) glow discharge. We found that both the initial cell performance and stability of the MVHF a-Si:H single-junction cells are independent of the deposition rate up to 15 Å/s. The average initial and stable active-area cell efficiencies of 10.0% and 8.5%, respectively, were obtained for the cells on textured Ag/ZnO coated stainless steel substrates. a-SiGe:H single-junction cells were also optimized at a rate of ~10 Å/s. The cell performance is similar to those made using conventional radio frequency technique at 3 Å/s. By combining the optimized component cells made at 10 Å/s, an a-Si:H/a-SiGe:H double-junction solar cell with an initial active-area efficiency of 11.7% was achieved.

Mechanism of High Rate a-Si:H Deposition in a VHF Plasma

1993 ◽  
Vol 297 ◽  
Author(s):  
M. Heintze ◽  
R. Zedlitz ◽  
G.H. Bauer
Keyword(s):  
Optical Emission ◽  
Impedance Analysis ◽  
High Energy ◽  
High Rate ◽  
Growth Surface ◽  
Very High Frequency ◽  
Ion Energy ◽  
Glow Discharges ◽  
Radical Generation ◽  
Very High

Very high frequency (VHF) glow discharges are employed for high rate a-Si:H deposition while maintaining good optoelectronic materials properties. A more efficient radical generation, either due to higher electron densities or an enhanced high energy electron tail is generally assumed as the mechanism. We have investigated a VHF a-Si:H deposition plasma between 40 and 250MHz by optical emission spectroscopy (OES), mass spectroscopy (MS), ion energy measurements and electrical impedance analysis. The present study shows that the increase of the deposition rate with frequency is essentially due to an enhanced ion flux to the growth surface.

High-Rate Deposition of Intrinsic Amorphous Silicon Layers for Solar Cells Using Very High Frequency Plasma at Atmospheric Pressure

2006 ◽  
Vol 45 (4B) ◽  
pp. 3587-3591 ◽  
Author(s):  
Hiroaki Kakiuchi ◽  
Hiromasa Ohmi ◽  
Yasuhito Kuwahara ◽  
Mitsuhiro Matsumoto ◽  
Yusuke Ebata ◽  
...  
Keyword(s):  
Solar Cells ◽  
Amorphous Silicon ◽  
Atmospheric Pressure ◽  
High Frequency ◽  
High Rate ◽  
Very High Frequency ◽  
High Frequency Plasma ◽  
Frequency Plasma ◽  
Very High

IN-SITU SPECTRAL ANALYSIS OF VERY HIGH FREQUENCY GLOW DISCHARGE (VHF-GD)

2002 ◽  
Vol 16 (28n29) ◽  
pp. 4475-4478 ◽  
Author(s):  
HUIDONG YANG ◽  
CHUNYA WU ◽  
SHAOZHENG XIONG ◽  
YAOHUA MAI ◽  
HONGBO LI ◽  
...  
Keyword(s):  
Excitation Frequency ◽  
Emission Spectra ◽  
Optical Emission ◽  
Excitation Power ◽  
Dilution Ratio ◽  
Very High Frequency ◽  
Hydrogen Dilution ◽  
Optical Emission Spectra ◽  
Very High

The intensities of SiH*, [Formula: see text] and H* of VHF-GD for depositing μc-Si:H were much higher than those of RF-GD for depositing a-Si:H. The SiH* intensity of VHF-GD became higher than its Si* intensity as the hydrogen dilution ratio decreased. The influences of the hydrogen dilution ratio on the plasma optical emission spectra also depended on the reaction pressure, the excitation power as well as the excitation frequency.

High Rate Deposition of Stable Hydrogenated Amorphous Silicon in Transition from Amorphous to Microcrystalline Silicon

2003 ◽  
Vol 762 ◽  
Author(s):  
Guofu Hou ◽  
Xinhua Geng ◽  
Xiaodan Zhang ◽  
Ying Zhao ◽  
Junming Xue ◽  
...  
Keyword(s):  
Phase Transition ◽  
Amorphous Silicon ◽  
Hydrogenated Amorphous Silicon ◽  
Chemical Vapor ◽  
High Rate ◽  
Very High Frequency ◽  
High Quality ◽  
Working Pressure ◽  
Hydrogen Dilution ◽  
Hydrogenated Amorphous

AbstractHigh rate deposition of high quality and stable hydrogenated amorphous silicon (a-Si:H) films were performed near the threshold of amorphous to microcrystalline phase transition using a very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD) method. The effect of hydrogen dilution on optic-electronic and structural properties of these films was investigated by Fourier-transform infrared (FTIR) spectroscopy, Raman scattering and constant photocurrent method (CPM). Experiment showed that although the phase transition was much influenced by hydrogen dilution, it also strongly depended on substrate temperature, working pressure and plasma power. With optimized condition high quality and high stable a-Si:H films, which exhibit σph/σd of 4.4×106 and deposition rate of 28.8Å/s, have been obtained.

scholarly journals Effect of Thermal Annealing on the Photoluminescence of Dense Si Nanodots Embedded in Amorphous Silicon Nitride Films

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 354
Author(s):  
Qianqian Liu ◽  
Xiaoxuan Chen ◽  
Hongliang Li ◽  
Yanqing Guo ◽  
Jie Song ◽  
...  
Keyword(s):  
Silicon Nitride ◽  
Amorphous Silicon ◽  
Thermal Annealing ◽  
Chemical Vapor ◽  
Peak Position ◽  
Excitation Wavelength ◽  
Very High Frequency ◽  
Amorphous Silicon Nitride ◽  
Silicon Nitride Films ◽  
High Frequency Plasma

Luminescent amorphous silicon nitride-containing dense Si nanodots were prepared by using very-high-frequency plasma-enhanced chemical vapor deposition at 250 °C. The influence of thermal annealing on photoluminescence (PL) was studied. Compared with the pristine film, thermal annealing at 1000 °C gave rise to a significant enhancement by more than twofold in terms of PL intensity. The PL featured a nanosecond recombination dynamic. The PL peak position was independent of the excitation wavelength and measured temperatures. By combining the Raman spectra and infrared absorption spectra analyses, the enhanced PL was suggested to be from the increased density of radiative centers related to the Si dangling bonds (K0) and N4+ or N20 as a result of bonding configuration reconstruction.

Sign in / Sign up

Export Citation Format

Share Document