Fabrication of InN based photodetector using porous silicon buffer layer

Abstract

We fabricated indium nitride (InN) on porous silicon (PSi) on crystalline silicon [Si(100)] heterostructure photodetector via radio frequency sputtering. PSi layer was synthesised on n type Si(100) wafers via photoelectrochemical etching. Large area PSi, which comprised an array of voids, was used as an intermediate layer between Si and InN thin film. X-ray diffraction results revealed that nanocrystalline wurtzite structure of InN thin film with preferred orientations of InN (101) was deposited on PSi/Si(100) substrate. Nickel Schottky contact was fabricated on InN thin films via thermal vacuum evaporation using a metal semiconductor metal mask. To relieve stress and to induce any favourable reactions between the metals and the semiconductors, the InN photodetector was annealed in an N2 environment. Current–voltage measurements after heat treatment at 400°C were performed in the dark and illuminated conditions.