Fabrications and Characteristics of Ⅲ-ⅤCompounds Multi-Junction Solar Cells and PIN Silicon Thin Films Solar Cells

• Main Authors: W.C. Hsieh, 謝文章
• Other Authors: Yu-Zung Chiou
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/53730773229023469313

碩士 === 南台科技大學 === 電子工程系 === 97 === In this study, we found that the efficiency of the well-fabricated multi-junction solar cells was only 0.982%. By using the IPCE measurement, we found that the solar cells almost did not react with visible light. We supposed that GaAs contact layer absorbed the visible light, so that the devices did not react with visible light. For verifying this supposing, we etched the GaAs contact, and the efficiency could be improved from 0.982% to 2.63%. But the devices did not react with visible light on IPCE measurement. So we supposed the InGaP cell caused the issue. For making sure the supposing, we etched the InGaP epitaxial layers by wet etching, and measured the transforming efficiency. The efficiency of the single junction GaAs solar cells was 9.31%. And the devices did react with visible light on IPCE measurement. So InGaP epitaxial layers caused the bad efficiency. On the Si thin film solar cells, we first grew the p-type Si thin film by changing fabrication power and fabrication pressure, and analyzed the thin films with same thickness but different fabrication conditions. We found that the thin films had better resistivity and carrier concentration at high power and low pressure. So we merged the two conditions to fabricate the best p-type Si thin films. And we used the same method to fabricate intrinsic Si and n-type Si thin films. The intrinsic and n-type thin films grown by high power and low pressure fabricating had better resistivity and carrier concentration as well. Finally, we used p-type, intrinsic, n-type layers to fabricate PIN solar cells. For efficiency measurement, the devices showed almost zero efficiency. This problem may caused by the amorphous Si thin films with many defects. So the devices did not have transforming efficiency.