6-Chemical configuration of hybrid layer in tunneling PV device
作者单位：SHU-SOEN’s R&DLabDepartment of PhysicsCollege of SciencesShanghai University
会议名称：《第六届新型太阳能电池材料科学与技术学术研讨会》
会议日期：2019年
学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）]
关 键 词：Amorphous SiOx layer Density functional theory Charge transition levels Tunneling
摘 要：Going into a hybrid silicon-based oxide layer with transition metals between TCO and Silicon to well understand its chemical configuration and electronic state is significant for the heterojunction photovoltaic devices, especially, for the two ends tandem PV of PSCs upon SHJ. At present, an amorphous silica layer containing In or Mo component(a-SiO(In,Mo) ～1.5-2.0 nm), as an example, is naturally formed in the process of PVD technique including sputtering or evaporating TCO onto n-type silicon, which plays a significant role on the non-equilibrium carriers’ transport of TCO/n-Si photovoltaic device [1]. The electronic structure and the charge transition levels of the amorphous silicon oxide doped with In or Mo are derived from density functional theory(DFT). The DOS show that the extensional or local states are existed in the band gap of amorphous silicon oxide, caused by the hybridization of electron orbital. The charge transition level of ε(+1/0) is located above the valance band maximum of a-SiO(In, Mo), which could be a passageway of carriers produced in the opto-electric conversion. The quantum transport mechanism from direct tunneling and defects level-assisted is put forwarded to explain the transport phenomenon in the novel PV device. Furthermore, the matching of work function for both TCO and Si is fundamental in the asymmetric device.