Initiating polarity inversion in GaN growth using an AlN interlayer

In this work, we show that the polarity of GaN grown on N‐polar material can be controlled through a combination of surface conditioning and introduction of a non‐Mg inversion layer (IL). The IL we use is a thin, low‐temperature AlN layer deposited by metal organic chemical vapor deposition (MOCVD). The subsequent inverted films are Ga‐polar that do not contain inversion domain boundaries and with crystal quality similar to MOCVD films grown on sapphire. The polarity inversion technique is enhanced by the addition of an etching step prior to AlN deposition.