METHOD OF FABRICATING A GALLIUM NITRIDE MERGED P-I-N SCHOTTKY (MPS) DIODE BY REGROWTH AND ETCH BACK

摘要

An MPS diode includes a III-nitride substrate characterized by a first conductivity type and a first dopant concentration and having a first side and a second side. The MPS diode also includes a III-nitride epitaxial structure comprising a first III-nitride epitaxial layer coupled to the first side of the substrate, wherein a region of the first III-nitride epitaxial layer comprises an array of protrusions. The III-nitride epitaxial structure also includes a plurality of III-nitride regions of a second conductivity type, each partially disposed between adjacent protrusions. Each of the plurality of III-nitride regions of the second conductivity type comprises a first section laterally positioned between adjacent protrusions and a second section extending in a direction normal to the first side of the substrate. The MPS diode further includes a first metallic structure electrically coupled to one or more of the protrusions and to one or more of the second sections.

主权项

1. A method for fabricating a merged P-i-N Schottky (MPS) diode in gallium nitride (GaN) based materials, the method comprising:
providing a n-type GaN-based substrate having a first surface and a second surface; forming an n-type GaN-based epitaxial layer coupled to the first surface of the n-type GaN-based substrate; removing a portion of the n-type GaN-based epitaxial layer to form a plurality of protrusions extending to a predetermined distance from the first surface of the GaN-based substrate; forming a p-type GaN-based epitaxial layer using a blanket regrowth process; removing a portion of the p-type GaN-based epitaxial layer to expose surfaces of the n-type GaN-based epitaxial layer, the exposed surfaces having p-type GaN-based regions disposed therebetween; forming a first metallic structure electrically coupled to the exposed surfaces of the n-type GaN-based epitaxial layer and the p-type GaN-based regions, wherein a Schottky contact is formed between the first metallic structure and the exposed surfaces of the n-type GaN-based epitaxial layer; and forming a second metallic structure electrically coupled to the second surface of the n-type GaN-based substrate.