Large-Area Hydrogenated Amorphous and Microcrystalline Silicon Double-Junction Solar Cells

2004 ◽  
Vol 808 ◽  
Author(s):  
Baojie Yan ◽  
Guozhen Yue ◽  
Arindam Banerjee ◽  
Jeffrey Yang ◽  
Subhendu Guha
Keyword(s):  
Solar Cells ◽  
Deposition Time ◽  
High Rate ◽  
Microcrystalline Silicon ◽  
Large Area ◽  
Area Efficiency ◽  
Rf Glow Discharge ◽  
Double Junction ◽  
Junction Structure ◽  
Hydrogenated Amorphous

ABSTRACTHydrogenated amorphous silicon (a-Si:H) and hydrogenated microcrystalline silicon ( c-Si:H) double-junction solar cells were deposited on a large-area substrate using a RF glow discharge technique at various rates. The thickness uniformity for both a-Si:H and c-Si:H is well within ± 10% and the reproducibility is very good. Preliminary results from the large-area a-Si:H/m c-Si:H double-junction structures show an initial aperture-area efficiency of 11.8% and 11.3%, respectively, for 45 cm2 and 461 cm2 size un-encapsulated solar cells. The 11.3% cell became 10.6% after encapsulation and stabilized at 9.5% after prolonged light soaking under 100 mW/cm2 of white light at 50°C. High rate deposition of the c-Si:H layer in the bottom cell was made using the high-pressure approach. An initial active-area (0.25 cm2) efficiency of 11.3% was achieved using an a-Si:H/m c-Si:H double-junction structure with 50 minutes of c-Si:H deposition time.

scholarly journals High-rate deposition of microcrystalline silicon in a large-area PECVD reactor and integration in tandem solar cells

2010 ◽  
pp. n/a-n/a ◽  
Author(s):  
Gaetano Parascandolo ◽  
Grégory Bugnon ◽  
Andrea Feltrin ◽  
Christophe Ballif
Keyword(s):  
Solar Cells ◽  
High Rate ◽  
Microcrystalline Silicon ◽  
Large Area ◽  
Tandem Solar Cells

Hydrogenated Microcrystalline Silicon Solar Cells Made with Modified Very-High-Frequency Glow Discharge

2002 ◽  
Vol 715 ◽  
Author(s):  
Baojie Yan ◽  
Kenneth Lord ◽  
Jeffrey Yang ◽  
Subhendu Guha ◽  
Jozef Smeets ◽  
...  
Keyword(s):  
Solar Cells ◽  
Glow Discharge ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Microcrystalline Silicon ◽  
Very High Frequency ◽  
Area Efficiency ◽  
Double Junction ◽  
Stability Data ◽  
The Stability

AbstractHydrogenated microcrystalline silicon (μc-Si:H) solar cells are made using modified veryhigh-frequency (MVHF) glow discharge at deposition rates ∼3-5 Å/s. We find that the solar cells made under certain conditions show degradation in air without intentional light soaking. The short-circuit current drops significantly within a few days after deposition, and then stabilizes. We believe that post-deposition oxygen diffusion along the grain boundaries or cracks is the origin of the ambient degradation. By optimizing the deposition conditions, we have found a plasma regime in which the μc-Si:H solar cells do not show such ambient degradation. The best a-Si:H/μc-Si:H double-junction solar cell has an initial active-area efficiency of 10.9% and is stable against the ambient degradation. The stability data of the solar cells after light soaking are also presented.

11.0% Stable Efficiency on Large Area, Encapsulated a-Si:H and a-SiGe:H based Multijunction Solar Cells Using HF Technology

2011 ◽  
Vol 1321 ◽  
Author(s):  
A. Banerjee ◽  
D. Beglau ◽  
T. Su ◽  
G. Pietka ◽  
G. Yue ◽  
...  
Keyword(s):  
Solar Cells ◽  
Triple Junction ◽  
Gas Flow ◽  
High Efficiency ◽  
Open Circuit ◽  
Large Area ◽  
Multijunction Solar Cells ◽  
Double Junction ◽  
Junction Structure ◽  
Cell Thickness

ABSTRACTWe report on the investigation of large area a-Si:H/a-SiGe:H double-junction and a-Si:H/a-SiGe:H/a-SiGe:H triple-junction solar cells prepared by our proprietary High Frequency (HF) glow discharge technique. For investigative purposes, we initially used the simpler double-junction structure. We studied the effect of: (1) Ge content, (2) cell thickness, and (3) SiH4 and GeH4 gas flow on the light-induced degradation of the solar cells. Our results show that the double-junction cells with different Ge concentration have open-circuit voltage (Voc) in the range of 1.62-1.75 V. Voc exhibits a flat plateau in the range of 1.65-1.72 V for both initial and stabilized states. The light-induced degradation for cells in this range of Voc is insensitive to the Ge content. In terms of thickness dependence of the intrinsic layers, we found that the initial efficiency increases with cell thickness in the thickness range 2000-4000 Å. However, light-induced degradation increases with increasing thickness. Consequently, the stabilized efficiency is invariant with cell thickness in the thickness range studied. The results of SiH4 and GeH4 gas flow on cell characteristics demonstrate that the deposition rate decreases by only 20% when the active gas flow is reduced to 0.25 times standard flow. The initial and stabilized efficiencies are similar. The information gleaned from the study was used to fabricate high efficiency, large area (~464 cm2) double- and triple-junction solar cells. The highest stable efficiency, as measured by NREL, was 9.8% and 11.0% for the double- and triple-junction structures, respectively.

Microcrystalline Silicon Thin Films and Triple-Junction Solar Cells

2012 ◽  
Vol 468-471 ◽  
pp. 1912-1915
Author(s):  
Hui Zhi Ren ◽  
Ying Zhao ◽  
Xiao Dan Zhang ◽  
Hong Ge ◽  
Zong Pan Wang
Keyword(s):  
Thin Films ◽  
Solar Cells ◽  
Triple Junction ◽  
Microcrystalline Silicon ◽  
Large Area ◽  
High Quality ◽  
Area Efficiency ◽  
Silicon Thin Films ◽  
Deposition Parameters ◽  
Area Deposition

We report on microcrystalline silicon thin films and a-Si:H/a-SiGe:H/μc-Si:H triple-junction p-i-n solar cells deposited on large-area glass substrate. Microcrystalline silicon (μc-Si:H) bottom cells were deposited at a VHF-PECVD deposition system with 40.68MHz. It is necessary to develop the uniformity of μc-Si:H thin films for large-area deposition of high-quality triple-junction solar cells. By optimizing the deposition parameters, μc-Si:H thin films have been obtained with good thickness and very good crystalline volume fractions uniformity over the whole substrates area. The triple-junction module have been successful fabricated. The best module on 0.79 m2 size substrates has an initial total-area efficiency of 8.35%.

Amorphous Silicon Alloy Solar Cells Near the Threshold of Amorphous-to-Microcrystalline Transition

2000 ◽  
Vol 609 ◽  
Author(s):  
Jeffrey Yang ◽  
Kenneth Lord ◽  
Subhendu Guha ◽  
S.R. Ovshinsky
Keyword(s):  
Solar Cells ◽  
Amorphous Silicon ◽  
High Efficiency ◽  
Open Circuit Voltage ◽  
Open Circuit ◽  
Area Efficiency ◽  
Junction Device ◽  
Tandem Structure ◽  
Double Junction ◽  
Junction Structure

ABSTRACTA systematic study has been made of amorphous silicon (a-Si) alloy solar cells using various hydrogen dilutions during the growth of the intrinsic (i) layer. We find that the open-circuit voltage (Voc) of the cells increases as the dilution increases; it then reaches a maximum before it decreases dramatically. This sudden drop in Voc is attributed to the transition from amorphous silicon to microcrystalline inclusions in the i layer. We study i-layer thicknesses ranging from 1000 Å to 5000 Å and find that the transition occurs in all thicknesses investigated. Based on this study, a-Si alloy p i n solar cells suitable for use in the top cell of a high efficiency triple-junction structure are made. By selecting an appropriate dilution, cells with Voc greater than 1 V can be achieved readily. Solar cells made near the threshold not only exhibit higher initial characteristics but also better stability against light soaking. We have compared top cells made near the threshold with our previous best data, and found that both the initial and stable efficiencies are superior for the near-threshold cells. For an a-Si/a-Si double-junction device, a Voc value exceeding 2 V has been obtained using thin component cells. Thicker component cells give rise to an initial active-area efficiency of 11.9% for this tandem structure.

Study of Large Area a-Si:H and nc-Si:H Based Multijunction Solar Cells and Materials

2008 ◽  
Vol 1066 ◽  
Author(s):  
Xixiang Xu ◽  
Baojie Yan ◽  
Dave Beglau ◽  
Yang Li ◽  
Greg DeMaggio ◽  
...  
Keyword(s):  
Solar Cells ◽  
Deposition Rate ◽  
Plasma Deposition ◽  
Nanocrystalline Silicon ◽  
High Rate ◽  
High Deposition Rate ◽  
Large Area ◽  
Very High Frequency ◽  
Spatial Uniformity ◽  
Double Junction

ABSTRACTSolar cells based on hydrogenated nanocrystalline silicon (nc-Si:H) have demonstrated significant improvement in the last few years. From the standpoint of commercial viability, good quality nc-Si:H films must be deposited at a high rate. In this paper, we present the results of our investigations on obtaining high quality nc-Si:H and a-Si:H films and solar cells over large areas using high deposition rate. We have employed the modified very high frequency (MVHF) glow discharge technique to realize high-rate deposition. Modeling studies were conducted to attain good spatial uniformity of electric field over a large area (15”×1”) MVHF cathode for nc-Si:H deposition. A comparative study has been carried out between the RF and MVHF plasma deposited a-Si:H and nc-Si:H single-junction and a-Si:H/nc-Si:H double-junction solar cells. By optimizing the nc-Si:H cell and the tunnel/recombination junctions, we have obtained an initial aperture-area (460 cm2) efficiency of 11.9% for a-Si:H/nc-Si:H double-junction cells using conventional RF (13.56 MHz) plasma deposition. The deposition rate was 3 Å/sec. Results on solar cells made with MVHF will also be presented.

High Quality a-SiO:H Films and Their Application to a-Si Solar Cells

1992 ◽  
Vol 258 ◽  
Author(s):  
S. Fujikake ◽  
H. Ohta ◽  
A. Asano ◽  
Y. Ichikawa ◽  
H. Sakai
Keyword(s):  
Solar Cells ◽  
Silicon Oxide ◽  
Hydrogenated Amorphous Silicon ◽  
Gas Mixture ◽  
High Quality ◽  
Area Efficiency ◽  
Si Solar Cells ◽  
Rf Glow Discharge ◽  
Amorphous Silicon Oxide ◽  
Hydrogenated Amorphous

ABSTRACTHydrogenated amorphous silicon oxide (a-SiO:H) films were prepared by rf glow discharge decomposition of SiH4, CO2 and H2 gas mixture. These films showed better properties than a-SiC:H films. By applying the a-SiO:H to the p-layer, we attained an efficiency of 12.5% for 1cm2 single junction solar cells and a total-area efficiency of 10.1% for 30cm × 40cm tandem submodules.

Temperature Dependence of Protocrystalline Silicon/Microcrystalline Silicon Double-Junction Solar Cells

2008 ◽  
Vol 47 (3) ◽  
pp. 1496-1500 ◽  
Author(s):  
Kobsak Sriprapha ◽  
Seung Yeop Myong ◽  
Akira Yamada ◽  
Makoto Konagai
Keyword(s):  
Solar Cells ◽  
Temperature Dependence ◽  
Microcrystalline Silicon ◽  
Double Junction

Towards Stabilized 10% Efficiency of Large-Area (> 5000cm2) a-Si/a-SiGe Tandem Solar Cells using High-Rate Deposition

2001 ◽  
Vol 664 ◽  
Author(s):  
Shingo Okamoto ◽  
Akira Terakawa ◽  
Eiji Maruyama ◽  
Wataru Shinohara ◽  
Makoto Tanaka ◽  
...  
Keyword(s):  
Solar Cells ◽  
Layer Structure ◽  
High Rate ◽  
Plasma Cvd ◽  
Large Area ◽  
Tandem Solar Cells ◽  
Cvd Method ◽  
Hydrogen Dilution ◽  
High Photosensitivity ◽  
Deposition Conditions

ABSTRACTThis paper reviews recent progress in large-area a-Si/a-SiGe tandem solar cells in Sanyo. Much effort has been devoted to increasing both the stabilized efficiency and the process throughput. A key issue in increasing the stabilized efficiency is thinner i-layer structure with an improved optical confinement effect. High-rate deposition of the i-layers has been investigated using rf (13.56MHz) plasma-CVD method while keeping the substrate temperature below 200 °C. A high photosensitivity of 106 of a-Si:H films maintain up to the deposition rate (Rd) of 15 Å/s by optimizing hydrogen dilution and other deposition conditions. It is of great importance to utilize the effect of hydrogen dilution which can reduce the incorporation of excess hydrogen in the films. The world's highest conversion efficiency of 11.2% has been achieved for a large-area (8252cm2) a-Si/a-SiGe tandem by combining the optimized hydrogen dilution and other solar cell related technologies.

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