Method for producing a semiconductor device comprising a Schottky diode and a high electron mobility transistor

A method for producing a semiconductor device that includes a Schottky diode and a High Electron Mobility Transistor (HEMT), the method comprising:

• producing a III-nitride stack on a carrier substrate, the stack including at least a lower III-nitride layer and an upper III-nitride layer forming a heterojunction therebetween, wherein a 2-dimensional electron gas (2DEG) layer may be formed in the lower III-nitride layer;
• depositing a dielectric layer on the III-nitride stack;
• patterning the dielectric layer to form a plurality of openings through the dielectric layer, wherein the openings correspond to locations of anode and cathode electrodes of the Schottky diode and to locations of source, drain, and gate electrodes of the HEMT, wherein one or more of the openings are anode-openings that correspond to the location of the anode electrode, wherein the one or more anode-openings include a first portion corresponding to a Schottky junction of the Schottky diode and a second portion that is adjacent to the first portion, and wherein each opening of the second portion is located between the first portion and one of one or more openings that correspond to the cathode electrode;
• producing one or more first layers of a doped III-nitride material in the second portion of the one or more anode-openings, and producing one or more second layers of a doped III-nitride material in the one or more gate-openings that correspond to the gate electrode of the HEMT, wherein thicknesses of the first and second layers of doped III-nitride are not equal;
• producing the anode and cathode electrodes and the source, gate, and drain electrodes, wherein one or more portions of the anode are produced on top of the one or more first layers of the doped III-nitride material, and wherein the gate electrode is produced on top of the one or more second layers of the doped III-nitride material;
• and
• producing an isolation area between the Schottky diode and the HEMT.