Semiconductor device and method for producing the same

A vertical semiconductor device including a GaN-based stacked layer having an opening,

• the GaN-based stacked layer including n-type GaN-based drift layer/p-type GaN-based barrier layer/n-type GaN-based contact layer in that order to a top layer side, the opening extending from a top layer and reaching the n-type GaN-based drift layer, the semiconductor device comprising:
• a regrown layer located so as to cover a wall surface and a bottom portion of the opening, the regrown layer including an electron drift layer and an electron source layer;
• a source electrode that is in contact with the regrown layer, the n-type GaN-based contact layer, and the p-type GaN-based barrier layer;
• a gate electrode located above the regrown layer in the opening;
• and
• a bottom insulating layer located below the gate electrode and only in the bottom portion of the opening,
• wherein the regrown layer covers the wall surface of the opening and is terminated at the n-type GaN-based drift layer that forms the bottom portion of the opening, and the bottom insulating layer is located so as to cover the n-type GaN-based drift layer that is located in the bottom portion of the opening.

A vertical semiconductor device including a GaN-based stacked layer having an opening,

• the GaN-based stacked layer including n-type GaN-based drift layer/p-type GaN-based barrier layer/n-type GaN-based contact layer in that order to a top layer side, the opening extending from a top layer and reaching the n-type GaN-based drift layer, the semiconductor device comprising:
• a regrown layer located so as to cover a wall surface and a bottom portion of the opening, the regrown layer including an electron drift layer and an electron source layer;
• a source electrode that is in contact with the regrown layer, the n-type GaN-based contact layer, and the p-type GaN-based barrier layer;
• a gate electrode located above the regrown layer in the opening;
• a bottom insulating layer located below the gate electrode and only in the bottom portion of the opening;
• and
• an insulating layer located below the gate electrode and on the regrown layer, the insulating layer being disposed at least on the wall surface of the opening.