期刊
ACS APPLIED MATERIALS & INTERFACES
卷 7, 期 34, 页码 19282-19294出版社
AMER CHEMICAL SOC
DOI: 10.1021/acsami.5b05318
关键词
crystalline silicon; passivation; silicon dielectrics; plasma enhanced chemical vapor deposition; liquid phase crystallization
资金
- German Federal Ministry of Education and Research (BMBF)
- state government of Berlin (SENBWF) [03IS2151]
- German Federal Ministry for Economic Affairs and Energy (BMWi) in the DEMO14 project [0325237]
In this study, various silicon dielectric films, namely, a-SiOx:H, a-SiNx:H, and a-SiOxNy:H, grown by plasma enhanced chemical vapor deposition (PECVD) were evaluated for use as interlayers (ILs) between crystalline silicon and glass. Chemical bonding analysis using Fourier transform infrared spectroscopy showed that high values of oxidant gases (CO2 and/or N-2), added to SiH4 during PECVD, reduced the Si H and N H bond density in the silicon dielectrics. Various three layer stacks combining the silicon dielectric materials were designed to minimize optical losses between silicon and glass in rear side contacted hetero junction pn test cells. The PECVD grown silicon dielectrics retained their functionality despite being subjected to harsh subsequent processing such as crystallization of the silicon at 1414 degrees C or above. High values of short circuit current density (j; without additional hydrogen passivation) required a high density of Si H bonds and for the nitrogen containing films, additionally, a high N H bond density. Concurrently high values of both J and open circuit voltage Voc were only observed when [Si- H] was equal to or exceeded [N-H]. Generally, V with a high density of [Si I-] bonds in the silicon dielectric; otherwise, additional hydrogen passivation using an active plasma process was required. The highest V., 560 mV, for a silicon acceptor concentration of about 1016 cm(-3), was observed for stacks where an a-SiOx.Ny:H film was adjacent to the silicon. Regardless of the cell absorber thickness, field effect passivation of the buried silicon surface by the silicon dielectric was mandatory for efficient collection of carriers generated from short wavelength light (in the vicinity of the glass Si interface). However, additional hydrogen passivation was obligatory for an increased diffusion length of the photogenerated carriers and thus j in solar cells with thicker absorbers.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据