Fabrication of a GaN template with an air tunnel in a patterned sapphire substrate using carbonization with a photoresist mask

Abstract

We successfully fabricated a template with an air tunnel between a patterned sapphire substrate (PSS) and GaN using a photoresist mask. The photoresist mask was subjected to plasma etching to induce the growth of the GaN nucleus at the top of the mask by exposing only the top of the PSS lens to the mask height. The carbon profile of the photoresist mask was checked by secondary ion mass spectrometry to detect the presence or absence of carbon in the GaN template during the process. In order to confirm the carbon’s effect on the epitaxially grown GaN template, the XRD was confirmed by the pole figure and the rocking curve. In order to confirm the change of the energy level of GaN by forming a trap in the energy band by carbon, we confirmed the effect of the carbon by comparing the degree of pure GaN.