| 학회 | 한국재료학회 |
| 학술대회 | 2016년 가을 (11/16 ~ 11/18, 경주 현대호텔) |
| 권호 | 22권 2호 |
| 발표분야 | H. 한-일 재료공학 워크샵 |
| 제목 | Properties of spin-coated alumina passivation films for silicon solar cells |
| 초록 | Surface passivation for silicon solar cells is a key factor to improve cell efficiency. In recent years, alumina passivation films have attracted much attention because of high-level of passivation quality and large amount of negative fixed charge density. Since 2006, electronic properties of alumina passivation films for silicon solar cells have been widely investigated. Distinguished quality of alumina passivation films results from both the strong field effect passivation and high quality of chemical passivation [1]. At present, wide variety of methods has been applied to deposit alumina films on the wafers. Alumina films prepared by thermal and plasma-enhanced atomic layer deposition (ALD) technique indicated high passivation property for both p-type and n-type silicon wafers. In common, the passivation films have been mainly prepared by atomic layer deposition (ALD) at present. Wet process such as a sol-gel method is one of the candidates to prepare alumina passivation films inexpensively and easily. Our recent research revealed that the sol-gel prepared alumina passivation films using Al(acac)3 have moderate passivation quality [2]. Also, we evaluated different alumina precursors, aluminum isopropoxide (Al(O-i-Pr)3), and compared the passivation quality of the films using these precursors. Calcination temperature dependence of effective lifetime of the silicon substrates that were covered with sol-gel deposited passivation films were investigated. Measured effective lifetime vs. calcined temperature is shown in Fig. 1. The figure indicates that passivation effects arise above 400°C, and maximum effective lifetime appears around 500°C of calcination condition. On the other hand, the samples calcined at 300°C, there were no lifetime enhancement. Above 700°C, the passivation effect decreases, and this may be due to desorption of hydrogen atoms from the Si/alumina interface. Also, we applied the spin-coated alumina films for the use of back side passivation layer of silicon solar cells, and evaluate the effectiveness of the passivation layer. Here we prepared the cells with low-cost Cz p-type silicon wafers with Passivated Emitter and Rear Cell (PERC) structures without a surface texturing, and evaluate the cell efficiency versus the rear electrode contact size and aperture ratio dependence. Our results indicate that the spin-coated alumina passivation films with moderate passivation quality are also effective for low-cost silicon solar cells. |
| 저자 | Ryosuke WATANABE1, Ryo ITO2, Mizuho KAWASHIMA1, Yoji SAITO2 |
| 소속 | 1Seikei Univ., 2Japan |
| 키워드 | Surface passivation; Sol-gel; Silicon solar cells |
