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.