The Emitter Having Microcrystalline Surface in Silicon Heterojunction Interdigitated Back Contact Solar Cells

Abstract

In producing the Si heterojunction interdigitated backcontact solar cells, we investigated the feasibility of applying amorphous Si emitter having considerable crystalline Si phase at the facing to transparent conducting oxide (TCO) layer. Prior to evaluating electrical property, we characterized material nature of hydrogenated microcrystalline p-type silicon (mu c-p-Si:H) as crystallized fraction, surface morphology, bonding kinds in thin films and then surface passivation quality finally. The diode and interface contact characteristics were induced by the simple test device and then current-voltage (I-V) curve showed more linearity in mu c/hydrogenated amorphous silicon (a-Si:H) emitter case. We fabricated heterojunction back contact (HBC) solar cells using p/n interdigitated structure and acquired the 23.4% efficiency in cell size with performance parameters as open-circuit voltage (V-oc) 723 mV, short-circuit current density (J(sc)) 41.8 mA/cm(2), fill factor (FF) 0.774, in the cell size (at 2 x 2 cm(2)). (C) 2012 The Japan Society of Applied Physics