A systematic investigation has been made on output measurement of the a-Si//al-SiGe//a-SiGe triple stacked solar cells. Prototype modules incorporating triple a-Si cells fabricated in high deposition rate plasma CVD process with micro-wave power source[l] have been exposed outdoor for about a half to one year at three different geographical locations to evaluate the outdoor performance under cold, temperate and tropical climates. The results showed that a-Si performed better under higher temperature climate. Energy efficiency over 8% was obtained in Kuala Lumpur. Power rating under 1 sun, 50deg.C light soaking condition seems to be reasonable in Kyoto.

Two types of FNO compounds ͑FNO and F 3 NO) were evaluated as candidates for new chemical vapor deposition ͑CVD͒ chamber cleaning gases. NF 3 and C 2 F 6 were measured as the reference. Like NF 3 , as these gases have no carbon in their molecules, no perfluoro carbon ͑PFC͒ is thought to be emitted. FNO is a compound highly susceptible to hydrolysis. F 3 NO is expected to decompose more easily than NF 3 in the atmosphere because its N-F bond has been weakened by introducing an NϭO bond into the molecule. Hence, the contribution to global warming of these compounds is expected to be small. Performance of these gases was evaluated by measuring their etch rates and their exhaust gases. The results showed that the etch rate of F 3 NO is virtually the same as that of NF 3 , whereas the etch rate of FNO is about 1/2 that of NF 3 . However, from the results of exhaust gas analysis, it was found that an unexpected side reaction had occurred in the chamber, and therefore, it was confirmed that it is important to take this property into account in designing applications.

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