Solar cell operation of sputter-deposited n-BaSi2/p-Si heterojunction diodes and characterization of defects by deep-level transient spectroscopy

Abstract

Abstract We form carbon-doped n-BaSi2(0.35 μm)/p-Si(111) heterojunction diodes by radio-frequency sputtering using BaSi2 and SiC targets, and demonstrate the solar cell operation for the first time under AM1.5 illumination. The electron trap level was measured to be 0.21 eV below the conduction band edge of the n-BaSi2 layers by deep-level transient spectroscopy. The shunt resistance reflecting the quality of the heterointerface exceeds 0.7 MΩ, one order of magnitude higher than that obtained for the same structure grown by molecular beam epitaxy. The carrier transport properties are discussed based on the external quantum efficiency spectrum and the band alignment.