PEDOT:PSS-mediated semiconductor wafer bonding for built-in middle subcells in multijunction solar cells

Abstract

We propose and experimentally demonstrate a novel concept of semiconductor wafer bonding that simultaneously realizes bond formation and solar cell implementation. Firstly, a semiconductor bonding technique mediated by poly(3, 4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is developed. By utilizing the PEDOT:PSS-mediated bonding, we subsequently fabricate an InP/Si heterostructure. The PEDOT:PSS/Si heterojunction derivatively formed at the bonded interface is then demonstrated to operate as a photovoltaic device. The prepared InP/PEDOT:PSS/Si heterostructure can thus be regarded as a prototype architecture representing an intermediate section of a multijunction solar cell with a built-in subcell. Our facile semiconductor bonding scheme mediated by functional agents could lead to low-cost, high-throughput production of high-efficiency multijunction solar cells.