Gallium nitride (GaN) offers significant performance benefits for a wide range of analog microchips, from RF-ICs to numerous power control ICs such as high-power HEMTs used in communications, energy, and military applications. GaN is also the material of choice for high-brightness LEDs used in highly energy-efficient solid-state lighting.
However, the best-quality single-crystal GaN is grown via several epitaxial processes requiring expensive single-use silicon carbide (SiC) substrates, which has limited its commercialization into broader markets, including consumer electronics. A recent discovery by IBM T.J. Watson Research Center scientists may change all of that, in a single crystal GaN film growth process called direct van der Waals epitaxy.
The compelling research finding has targeted the use of recyclable SiC substrates with graphene overlayers for the growth of GaN films based on the process flow depicted in figure 1.
Graphene on silicon-carbide produces a reusable growth substrate for GaN.