Preparation of High-Quality a-SiGe:H films with Low Impurity Oncentration by the Hydrogen Dilution Method

1991 ◽  
Vol 219 ◽  
Author(s):  
Katsunobu Sayama ◽  
Hisao Haku ◽  
Hiroshi Dohjoh ◽  
Masao Isomura ◽  
Noboru Nakamura ◽  
...  

ABSTRACTA-SiGe: H film properties with a low impurity concentration were investigated using a super chamber in the range of Ge content of 0% to 36%. These a-SiGe films can maintain a high photosensitivity of about 106 for Ge content up to 13%, which is comparable to high-quality a~Si films. It was found that impurity incorporation deteriorates optoelectronic properties in the range of a small amount of Ge content, and film rigidity in the range of a large amount of Ge content. Using high-quality a-SiGe films with a low impurity concentration in solar cells, the highest conversion efficiency of 3.15% was obtained for an a-SiGe single-junction cell under red light (AM-1.5, 100mW/cm2 light through the optical filter, in which the wavelength of transmitted light is longer than 650nm). A stacked cell of a-Si/a-Si/a-SiGe has a conversion efficiency of 11.9%.

1987 ◽  
Vol 95 ◽  
Author(s):  
Shinya Tsuda ◽  
Hisao Haku ◽  
Hisaki Tarui ◽  
Takao Matsuyama ◽  
Katsunobu Sayama ◽  
...  

AbstractIn order to improve the conversion efficiency of a-Si solar cells, high-quality a-Si based alloys of both narrow handgap and wide bandgap were studied.Concerning the narrow bandgap material, we found a particular dependence of film qualities on substrate temperature. In addition, high-quality a-SiGe:H films were obtained by using a super chamber (separated ultra-high vacuum reaction chamber).As for the high-quality wide bandgap material, a-Si/a-SiC superlattice structure films fabricated by a photo-CVD method were studied for the first time. From the analysis of their properties, we found that the superlattice structure p-layer was an active layer for photovoltaic effect. A conversion efficiency of 11.2% has been obtained for a pin a-Si solar cell whose player was of the superlattice structure.


1986 ◽  
Vol 70 ◽  
Author(s):  
Shoichi Nakano ◽  
Shinya Tsuda ◽  
Hisaki Tarui ◽  
Tsuyoshi Takahama ◽  
Hisao Haku ◽  
...  

ABSTRACTAs a new preparation method for high-quality a-Si films, we have developed the super chamber, a separated UHV reaction chamber system. A low impurity concentration and excellent film properties were obtained by the super chamber. A conversion efficiency of 11.7% was obtained for an a-Si solar cell using a high-quality i-layer deposited by the super chamber, and a p-layer fabricated by a photo-CVD method.As a new material, amorphous superlattice structure films were fabricated by the photo-CVD method for the first time. Quantization effects and low damage to the interfaces were observed. Superlattice structure p-layer a-Si solar cells were fabricated for the first time, and a conversion efficiency of 10.5% was obtained.


1989 ◽  
Vol 164 ◽  
Author(s):  
T. Matsuyama ◽  
M. Nishikuni ◽  
M. Kameda ◽  
S. Okamoto ◽  
M. Tanaka ◽  
...  

AbstractWe have achieved the highest total area conversion efficiency for an integrated type 10cm × 10cm a-Si solar cell at 10.2%. This value is the world record for a 10cm × 10cm a-Si solar cell. For further improvement of conversion efficiency in a-Si solar cells, it is necessary to develop materials with high-photosensitivity in the long wavelength region and materials with high conductivity. We have developed a Solid Phase Crystallization (SPC) method of growing a Si crystal at temperatures as low as 600°C. Using this method, thin-film polycrystalline silicon (poly-Si) with higP-photosensitivity in the long wavelength region and Hall mobility of 70cm2/V sec was obtained and quantum efficiency in the range of 800,∼ lO00nm was achieved up to 80% in the n-type poly-Si with grain size of about 2μm. We also succeeded in preparing a device-quality p-type microcrystalline silicon (μc-Si) using the SPC method at 620°C for 3 hours from the conventional plasma-CVD p-type amorphous silicon (a-5i) withoul using any post-doping process. Obtained properties of μd=2 × 103 (.cm) and a high optical transmittance in the 2.0 ∼ 3.0 eV range are better as a window material than the conventional p-type μc-Si:H. Therefore, it was concluded that the SPC method is better as a new technique to prepare high-quality solar cell materials.


2000 ◽  
Vol 609 ◽  
Author(s):  
Young J. Song ◽  
Elena Guliants ◽  
Hak-Gyu Lee ◽  
Wayne A. Anderson

ABSTRACTECR silane plasmas for the deposition of a-Si:H and μc-Si films were investigated by in-situ mass spectroscopy (MS) using a quadrupole residual gas analyzer. The results showed that the intensities of ionic and neutral species (H, H2, He, Ar, Si and SiHx) in the 2 % SiH4/He plasma are strongly dependent on the deposition conditions such as chamber pressure, input power and hydrogen dilution. In all cases, the prevalence of Si ions was observed over SiH, SiH2 and SiH3 ions, suggesting a high decomposition rate of the silane in the plasma. In particular, the population of atomic hydrogen in the plasma seems to play a key role in the properties of both a-Si:H and μc-Si films. For example, the increased intensity of atomic hydrogen, compared to that of molecular hydrogen, resulted in the better quality a-Si:H film, showing a higher photo and dark conductivity ratio of ~105. The intensity of the hydrogen species was especially sensitive to the chamber pressure. The correlation between MS spectra and film properties is presented.


2006 ◽  
Vol 515 (2) ◽  
pp. 452-455 ◽  
Author(s):  
Jinhua Gu ◽  
Meifang Zhu ◽  
Liujiu Wang ◽  
Fengzhen Liu ◽  
Bingqing Zhou ◽  
...  

1992 ◽  
Vol 242 ◽  
Author(s):  
K. Ninomiya ◽  
H. Haku ◽  
H. Tarui ◽  
N. Nakamura ◽  
M. Tanaka ◽  
...  

ABSTRACTA total area conversion efficiency of 11.1% has been achieved for a 1Ocm×1Ocm integrated-type single-junction a-Si solar cell submodule using a high-quality wide-bandgap p-layer doped with B(CH3)3 and other advanced techniques. This is the highest conversion efficiency ever reported for an a-Si solar cell with an area of 100cm2. As for a multi-junction solar cell, 12.1% was obtained for a 1cm2 cell with a high-quality wide-bandgap a-Si i-layer. The layer was fabricated by a hydrogen dilution method at a low substrate temperature for a front active layer of an a-Si/a-Si/a-SiGe stacked solar cell.For further improvement in conversion efficiency, a wider-bandgap a-SiC was developed using a novel plasma CVD method, called the CPM (Controlled Plasma Magnetron) method. From XPS and IR measurements, the resultant films were found to have high Si-C bond density and low Si-H bond density, p-type a-SiC was fabricated using the post-doping technique, and dark conductivity more than 10-5(Q. cm)-1 was obtained (Eopt3 ≥ 2eV; Eopt2 2.2eV), whereas that of conventional p-type a-SiC is less than 10-6(Ω·cm)-1. These properties are very promising for application to the p-layers of advanced a-Si solar cells.


1993 ◽  
Vol 297 ◽  
Author(s):  
E. Maruyama ◽  
Y. Yoshimine ◽  
A. Terakawa ◽  
K. Sayama ◽  
K. Ninomiya ◽  
...  

The quality of a-SiGe:H film was improved by considering the effects of substrate temperature and deposition rate on film properties. Accurate measurement of the optical gap and the film composition of Si, Ge and H made it possible to formulate the optical gap using a linear function of bonded H content (CH) and Ge content (CGE). It was found for the first time that, when the optical gap is fixed to a certain value, the optimum compositions of CHAand CGe exist for high-quality a-SiGe:H. Based on these, we obtained the world's highest conversion efficiency of 3.7 % under red light (AM-1.5, 100mW/cm2 through an R65 filter which allows passage of longer wavelength (>650nm) light) for a 1cm2 a-SiGe single-junction cell. Long-term stability of the cell was also improved.


2003 ◽  
Vol 762 ◽  
Author(s):  
Guofu Hou ◽  
Xinhua Geng ◽  
Xiaodan Zhang ◽  
Ying Zhao ◽  
Junming Xue ◽  
...  

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.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Lung-Chien Chen ◽  
Yi-Tsung Chang ◽  
Ching-Ho Tien ◽  
Yu-Chun Yeh ◽  
Zong-Liang Tseng ◽  
...  

AbstractThis work presents a method for obtaining a color-converted red light source through a combination of a blue GaN light-emitting diode and a red fluorescent color conversion film of a perovskite CsPbI3/TOPO composite. High-quality CsPbI3 quantum dots (QDs) were prepared using the hot-injection method. The colloidal QD solutions were mixed with different ratios of trioctylphosphine oxide (TOPO) to form nanowires. The color conversion films prepared by the mixed ultraviolet resin and colloidal solutions were coated on blue LEDs. The optical and electrical properties of the devices were measured and analyzed at an injection current of 50 mA; it was observed that the strongest red light intensity was 93.1 cd/m2 and the external quantum efficiency was 5.7% at a wavelength of approximately 708 nm when CsPbI3/TOPO was 1:0.35.


2017 ◽  
Vol 56 (47) ◽  
pp. 15078-15082 ◽  
Author(s):  
Xiao Yang ◽  
Li Ji ◽  
Xingli Zou ◽  
Taeho Lim ◽  
Ji Zhao ◽  
...  

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