Patent ID: 9577048
Date: 2017-02-21
CPC Classifications: H01L

Claim:
1. A heterostructure field-effect transistor (HFET), comprising: a substrate; a buffer layer disposed on the substrate; a channel layer disposed on the buffer layer and comprising a first group IIIA-VA compound semiconductor material; a barrier layer disposed on the channel layer and comprising a second group IIIA-VA compound semiconductor material; a gate disposed on the barrier layer; a source electrode; and a drain electrode, wherein the drain electrode includes a p-type semiconductor patterned structure and a raised drain section, the source electrode and the raised drain section are of the same metal material, the drain electrode includes a drain Schottky contact and a drain ohmic contact, the drain Schottky contact is formed between a top surface together with a side surface of the p-type semiconductor patterned structure and a first bottom surface together with a side surface of the raised drain section, the drain ohmic contact is formed between a second bottom surface of the raised drain section and the barrier layer, the raised drain section is partially surrounding the p-type semiconductor patterned structure, and a bandgap of the channel layer is less than a bandgap of the barrier layer.