Pulsed Sputtering Epitaxy of Coherent AlN/Al0.5Ga0.5N/AlN Multichannel Structures

Abstract

In this article, the advantages of AlN low‐temperature interface protective layer (LT‐IPL) prepared by sputtering epitaxy for the fabrication of AlN/Al0.5Ga0.5N/AlN multichannel device structures are discussed. In this study, it is found that the use of LT‐IPL enhances the AlN/AlGaN interface surface morphology and reduces AlN/Al0.5Ga0.5N/AlN multichannel structure misfit dislocations. This approach results in a coherent four‐channel AlN/AlGaN/AlN structure with considerably improved crystallinity. Moreover, consistent with predictions from 1D simulations, reductions in sheet resistance are inversely proportional to the number of channels. These advancements are pivotal for the development of sophisticated AlN/AlGaN/AlN multichannel structures, which are tailored for applications that require low resistance and high voltage.