Effects of hydrogen dilution grading in active layer on performance of nanocrystalline single junction bottom component and corresponding a-Si:H based triple junction solar cells

2006 ◽  
Author(s):  
Chandan Das ◽  
Xinmin Cao ◽  
Wenhui Du ◽  
Xiesen Yang ◽  
Yasuaki Ishikawa ◽  
...  
Keyword(s):  
Solar Cells ◽  
Active Layer ◽  
Triple Junction ◽  
Single Junction ◽  
Hydrogen Dilution

Metastability in hydrogenated nanocrystalline silicon solar cells

2007 ◽  
Vol 22 (5) ◽  
pp. 1128-1137 ◽  
Author(s):  
Guozhen Yue ◽  
Baojie Yan ◽  
Gautam Ganguly ◽  
Jeffrey Yang ◽  
Subhendu Guha
Keyword(s):  
Solar Cells ◽  
Band Gap ◽  
Amorphous Phase ◽  
Reverse Bias ◽  
Volume Fraction ◽  
Nanocrystalline Silicon ◽  
Silicon Solar Cells ◽  
Single Junction ◽  
Hydrogen Dilution ◽  
Forward Current

Light-induced metastability in hydrogenated nanocrystalline silicon (nc-Si:H) single-junction solar cells was studied systematically. First, we observed no light-induced degradation when the photon energy was lower than the band gap of the amorphous phase; degradation occurred when the energy was higher than the band gap in the amorphous phase. The light-induced degradation could be annealed away at an elevated temperature. We concluded that the light-induced defect generation occurred mainly in the amorphous phase. Second, forward current injection did not degrade the nc-Si:H cell performance. However, a reverse bias during light soaking enhanced the degradation. Third, the nc-Si:H cells made with an optimized hydrogen dilution profile showed minimal degradation although these cells had a high amorphous volume fraction. This indicated that the amorphous volume fraction was not the only factor determining the degradation. Other factors also played important roles in the nc-Si:H stability.

Stability of Single and Tandem Junction A-Si:H Solar Cells Grown using the ECR Process

1997 ◽  
Vol 467 ◽  
Author(s):  
Vikram L. Dalal ◽  
Tim Maxson ◽  
Robert Girvan ◽  
Sohail Haroon
Keyword(s):  
Solar Cells ◽  
Stability Studies ◽  
Stability Tests ◽  
High Hydrogen ◽  
Single Junction ◽  
Hydrogen Dilution ◽  
The Stability

ABSTRACTWe report on the fabrication and stability tests of single junction a-Si:H, and tandem junction a-Si:H/a-Si:H solar cells using the ECR process under high hydrogen dilution (H-ECR process). We show that devices with high fill factors can be made using the H-ECR process. We also report on the stability studies of the solar cells under 1 and 2-sun illumination conditions. The solar cells show very little degradation even after 500 hours of illumination under 2 x sunlight illumination.

Amorphous Silicon Alloy Materials and Solar Cells Near the Threshold of Microcrystallinity

1999 ◽  
Vol 557 ◽  
Author(s):  
J. Yang ◽  
S. Guha
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Amorphous Silicon ◽  
Triple Junction ◽  
High Efficiency ◽  
Spectral Response ◽  
High Quality ◽  
Silicon Alloys ◽  
Solar Cell Performance ◽  
Hydrogen Dilution

AbstractOne of the most effective techniques used to obtain high quality amorphous silicon alloys is the use of hydrogen dilution during film growth. The resultant material exhibits a more ordered microstructure and gives rise to high efficiency solar cells. As the hydrogen dilution increases, however, a threshold is reached, beyond which microcrystallites begin to form rapidly. In this paper, we review some of the interesting features associated with the thin film materials obtained from various hydrogen dilutions. They include the observation of linear-like objects in the TEM micrograph, a shift of the principal Si TO band in the Raman spectrum, a sharp, low temperature peak in the H2 evolution spectrum, a shift of the wagging mode in the IR spectrum, and a narrowing of the Si (111) peak in the X-ray diffraction pattern. These spectroscopic tools have allowed us to optimize deposition conditions to near the threshold of microcrystallinity and obtain desired high quality materials. Incorporation of the improved materials into device configuration has significantly enhanced the solar cell performance. Using a spectral-splitting, triple-junction configuration, the spectral response of a typical high efficiency device spans from below 350 nm to beyond 950 nm with a peak quantum efficiency exceeding 90%; the triple stack generates a photocurrent of 27 mA/cm2. This paper describes the effect of the improved materials on various solar cell structures, including a 13% active-area, stable triple-junction device.

High efficiency amorphous and nanocrystalline silicon based multi-junction solar cells deposited at high rates on textured Ag/ZnO back reflectors

2009 ◽  
Vol 1153 ◽  
Author(s):  
Guozhen Yue ◽  
Laura Sivec ◽  
Baojie Yan ◽  
Jeff Yang ◽  
Subhendu Guha
Keyword(s):  
Solar Cells ◽  
Triple Junction ◽  
High Efficiency ◽  
Nanocrystalline Silicon ◽  
Open Circuit ◽  
Very High Frequency ◽  
Solar Cell Performance ◽  
Single Junction ◽  
Back Reflectors ◽  
Back Reflector

AbstractWe report our recent progress on nc-Si:H single-junction and a-Si:H/nc-Si:H/nc-Si:H triple-junction cells made by a modified very-high-frequency (MVHF) technique at deposition rates of 10-15 Å/s. First, we studied the effect of substrate texture on the nc-Si:H single-junction solar cell performance. We found that nc-Si:H single-junction cells made on bare stainless steel (SS) have a good fill factor (FF) of ˜0.73, while it decreased to ˜0.65 when the cells were deposited on textured Ag/ZnO back reflectors. The open-circuit voltage (Voc) also decreased. We used dark current-voltage (J-V), Raman, and X-ray diffraction (XRD) measurements to characterize the material properties. The dark J-V measurement showed that the reverse saturated current was increased by a factor of ˜30 when a textured Ag/ZnO back reflector was used. Raman results revealed that the nc-Si:H intrinsic layers in the two solar cells have similar crystallinity. However, they showed a different crystallographic orientation as indicated in XRD patterns. The material grown on Ag/ZnO has more random orientation than that on SS. These experimental results suggested that the deterioration of FF in nc-Si:H solar cells on textured Ag/ZnO was caused by poor nc-Si:H quality. Based on this study, we have improved our Ag/ZnO back reflector and the quality of nc-Si:H component cells and achieved an initial and stable active-area efficiencies of 13.4% and 12.1%, respectively, in an a-Si:H/nc-Si:H/nc-Si:H triple-junction cell.

Correlation of Hydrogen Dilution Profiling to Material Structure and Device Performance of Hydrogenated Nanocrystalline Silicon Solar Cells

2008 ◽  
Vol 1066 ◽  
Author(s):  
Baojie Yan ◽  
Guozhen Yue ◽  
Yanfa Yan ◽  
Chun-Sheng Jiang ◽  
Charles W. Teplin ◽  
...  
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Cell Structure ◽  
Nanocrystalline Silicon ◽  
Cell Performance ◽  
Solar Cell Performance ◽  
Seeding Layer ◽  
Single Junction ◽  
Junction Solar Cell ◽  
Hydrogen Dilution

ABSTRACTWe present a systematic study on the correlation of hydrogen dilution profiles to structural properties materials and solar cell performance in nc-Si:H solar cells. We deposited nc-Si:H single-junction solar cells using a modified very high frequency (VHF) glow discharge technique on stainless steel substrates with various profiles of hydrogen dilution in the gas mixture during deposition. The material properties were characterized using Raman spectroscopy, X-TEM, AFM, and C-AFM. The solar cell performance correlates well with the material structures. Three major conclusions are made based on the characterization results. First, the optimized nc-Si:H material does not show an incubation layer, indicating that the seeding layer is well optimized and works as per design. Second, the nanocrystalline evolution is well controlled by hydrogen dilution profiling in which the hydrogen dilution ratio is dynamically reduced during the intrinsic layer deposition. Third, the best nc-Si:H single-junction solar cell was made using a proper hydrogen dilution profile, which caused a nanocrystalline distribution close to uniform throughout the thickness, but with a slightly inverse nanocrystalline evolution. We have used the optimized hydrogen dilution profiling and improved the nc-Si:H solar cell performance significantly. As a result, we have achieved an initial active-area cell efficiency of 9.2% with a nc-Si:H single-junction structure, and 15.4% with an a-Si:H/a-SiGe:H/nc-Si:H triple-junction solar cell structure.

Super High Efficiency Multi-Junction Solar Cells and Concentrator Solar Cells

2012 ◽  
pp. 2003-2023
Author(s):  
Masafumi Yamaguchi
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Triple Junction ◽  
High Efficiency ◽  
Single Junction ◽  
Key Issues ◽  
Cell Modules

While single-junction solar cells may be capable of attaining AM1.5 efficiencies of up to 29%, Multi-Junction (MJ, Tandem) III-V compound solar cells appear capable of realistic efficiencies of up to 50% and are promising for space and terrestrial applications. In fact, the InGaP/GaAs/Ge triple-junction solar cells have been widely used in space since 1997. In addition, industrialization of concentrator solar cell modules using III-V compound MJ solar cells have been announced by some companies. This chapter presents principles and key issues for realizing high-efficiency MJ solar cells, issues relating to development and manufacturing, and applications for space and terrestrial uses.

scholarly journals The efficiency of the single junction and multijunction InxGa1-xN solar cell using AMPS-1D simulator

2013 ◽  
Vol 37 (1) ◽  
pp. 65-72
Author(s):  
Md Fazlul Huq ◽  
Zamshed Iqbal Chowdhury ◽  
Mehedhi Hasan ◽  
Zahid Hasan Mahmood
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Band Gap ◽  
Conversion Efficiency ◽  
Triple Junction ◽  
Triple Junctions ◽  
Single Junction ◽  
Single Junction Solar Cell ◽  
Multijunction Solar Cell ◽  
Academy Of Sciences

Transparency loss and excess excitation loss are responsible for relatively lower conversion efficiency of single junction solar cell. One way to reduce these two losses is to use multijunction solar cell. In this research InxGa1-xN based single, double and triple junction solar cells were simulated employing AMPS-1D simulator. The band gap of each layer depends on the composition percentage of InN and GaN within InxGa1-xN. In this simulation the authors found 24.51, 33.89, and 42.12% efficiencies for single, double and triple junctions, respectively. DOI: http://dx.doi.org/10.3329/jbas.v37i1.15682 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 1, 65-72, 2013

He-Dilution to Increase Deposition Rate and Feedstock Utilization During the Growth of a-Si:H and a-SiGe:H Alloys

1999 ◽  
Vol 557 ◽  
Author(s):  
A. R. Middya ◽  
G. Wood ◽  
G. H. Lin ◽  
D. E. Carlson
Keyword(s):  
Solar Cells ◽  
Deposition Rate ◽  
State Of The Art ◽  
Deposition Rates ◽  
Single Junction ◽  
Hydrogen Dilution ◽  
Helium Dilution ◽  
Fabrication Time

AbstractWe report on the development of helium diluted a-Si:H and a-SiGe:H solar cells with higher deposition rates and better feedstock utilization than devices made with hydrogen dilution. Both the initial and the stabilized efficiencies of the He-diluted single-junction aSi:H and a-SiGe:H cells are similar to those of hydrogen-diluted cells with state-of-the-art intrinsic materials. The total fabrication time for tandem cells has been reduced by 17% by using helium dilution without loss in initial and stabilized efficiency.

Sign in / Sign up

Export Citation Format

Share Document