Structural, electrical and optical properties of ZnO/Si structures prepared by sputtering or pulsed laser deposition

Abstract

The present paper is based on study of polycrystalline ZnO:Al films deposited by RF sputtering in Ar atmosphere and by pulsed laser deposition (PLD) on p and n-type Si. The structural, electrical and optical properties of processed devices were investigated before and after annealing in temperature range of 400–600°C. Films deposited by RF sputtering show conductive ZnO:Al n-type layer. After annealing in N2 atmosphere the conductivity of ZnO layer increased as ZnO/Si interface exhibits diffusion of Si into ZnO and O into Si. This effect was confirmed show promising photodetector properties in the spectral range of 380 ÷ 1050 nm by SIMS depth profile measurements. PLD deposited ZnO films under certain growth conditions (400°C) in O2 atmosphere show p-type layer formation. The investigated Si/ZnO heterostructures shows promising photodetector properties in the spectral range of 380 ÷ 1050 nm.