Introducing Voids around the Interlayer of AlN by High Temperature Annealing

Abstract

Abstract To introduce voids at certain height in AlN layer by a simple method is meaningful but challenging. In this work, the AlN/sapphire template with AlN interlayer structure has been designed and grown by metal-organic chemical vapor deposition. Then the AlN template was annealed at 1700℃ for an hour to introduce the voids. It has been found that the voids were formed in the AlN layer after high temperature annealing and the positions of the voids were mainly distributed around the AlN interlayer. Meanwhile, the dislocation density of the AlN template has been decreased from 5.26×109 cm-2 to 5.10×108 cm-2. This work provides a possible method to introduce voids in AlN layer at designated height, which will benefit the design of AlN-based devices.