Towards Vertical GaN Power Transistors on Foreign Substrates: The European YESvGaN Project

Fabrication of vertical GaN power transistors on foreign instead of native substrates is an attractive route for the industrialization of vertical GaN technology as it circumvents high cost and small diameter of currently available GaN wafers. However, this approach requires to remove the substrate and epitaxial buffer layers under the active area resulting in a thin membrane transistor. This technology is currently developed in the EU-funded project YESvGaN. The consortium has demonstrated avalanche capability of GaN-on-sapphire epitaxial layers, processing of fully vertical Schottky diodes and first steps towards the assembly of such thin dies.