Lattice-matched multiple channel AlScN/GaN heterostructures

• DOI: 10.1063/5.0216133
• Publication Date: 2024-10-24T18:22:48Z
• Authors: Thai-Son Nguyen; Naomi Pieczulewski; Chandrashekhar Sa...; Joshua J. P. Cooper; Joseph Casamento; Rachel S. Goldman; David A. Muller; Huili G. Xing; Debdeep Jena
• Keywords: Lattice (music); Lattice constant

AlScN is a new wide bandgap, high-k, ferroelectric material for RF, memory, and power applications. Successful integration of high quality with GaN in epitaxial layer stacks depends strongly on the ability to control lattice parameters surface or interface through growth. This study investigates molecular beam epitaxy growth transport properties AlScN/GaN multilayer heterostructures. Single Al$_{1-x}$Sc$_x$N/GaN heterostructures exhibited lattice-matched composition within $x$ = 0.09 -- 0.11 using substrate (thermocouple) temperatures between 330 $ ^\circ$C 630 ^\circ$C. By targeting Sc composition, pseudomorphic structures ten twenty periods were achieved, exhibiting excellent structural as confirmed by X-ray diffraction (XRD) scanning transmission electron microscopy (STEM). These substantial polarization-induced net mobile charge densities up 8.24 $\times$ 10$^{14}$/cm$^2$ channels. The sheet density scales number periods. identifying condition it generate multiple conductive channels, this work enhances our understanding platform.