Patent ID: 9142631
Filing Date: 2015-09-22
Classification: H01L

Abstract:
1. A semiconductor Schottky barrier device comprising: a wide bandgap semiconductor layer comprising gallium nitride; a Schottky barrier metal layer on the wide bandgap semiconductor layer comprising gallium nitride and forming a Schottky junction therewith; a current spreading layer on the Schottky barrier metal layer remote from the wide bandgap semiconductor layer; a first diffusion barrier layer between the current spreading layer and the Schottky barrier metal layer; and a second diffusion barrier layer between the first diffusion barrier layer and the Schottky barrier metal layer; a third diffusion barrier layer between the second diffusion barrier layer and the Schottky barrier metal layer; and a fourth diffusion barrier layer between the third diffusion barrier layer and the Schottky barrier metal layer; wherein the second and fourth diffusion barrier layers comprise tantalum and/or tungsten, and wherein the Schottky barrier metal layer is directly on the wide bandgap semiconductor layer, the fourth diffusion barrier layer is directly on the Schottky barrier metal layer, the third diffusion barrier layer is directly on the fourth diffusion barrier layer, the second diffusion barrier layer is directly on the third diffusion barrier layer and the first diffusion barrier layer is directly on the second diffusion barrier layer.