Although difficult, it is not impossible to make GaN-on-GaN devices.
Many technology firms have significant programs under the GaN-on-Si umbrella, limiting the ability to invest in GaN-on-GaN technology and process. In addition, complex issues such as die size, wafer cost, wafer size (4″ GaN wafers vs. 6,8″ GaN-on-Si wafers); have led to the popular myth that GaN-on-GaN devices cannot be made.
NexGen has successfully built and sampled complete power systems with the world’s first commercially available GaN-on-GaN devices, NexGen Vertical GaN, switching at up-to 3MHz.