Method for Producing a Semiconductor Device Comprising a Schottky Diode and a High Electron Mobility Transistor

摘要

A semiconductor device includes a Schottky diode and a High Electron Mobility Transistor (HEMT) formed on a III-nitride stack. The III-nitride stack includes at least a lower and an upper III-nitride layer forming a heterojunction therebetween, so that a 2-dimensional electron gas (2DEG) layer may be formed in the lower layer. The 2DEG layer serves as a charge carrier for the diode and the HEMT. A doped III-nitride layer may be present between a portion of the anode of the diode and the III-nitride stack, and the portion may be located between the diode's Schottky junction and the cathode. A further layer of doped III-nitride material may be present between the gate electrode of the HEMT and the III-nitride stack. The thickness of the III-nitride layers is not equal, so that the turn-on voltage of the diode and the threshold voltage of the HEMT may be tuned according to specific requirements. The disclosure also involves a method of producing such a semiconductor device.

主权项

1. A semiconductor device comprising:
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; a Schottky diode comprising:
a cathode forming an ohmic contact with the upper III-nitride layer,an anode that includes a first portion that forms a Schottky barrier contact with the upper III-nitride layer and a second portion, the second portion being located between the first portion of the anode and the cathode,a first dielectric area on the upper III-nitride layer, wherein the first dielectric area isolates the anode and cathode from each other, anda first layer of doped III-nitride material between the second portion of the anode and the upper III-nitride layer, the doped III-nitride material being configured to pinch off the 2DEG layer in the reverse bias region of the Schottky diode; and a High Electron Mobility Transistor (HEMT) comprising:a source electrode and a drain electrode in ohmic contact with the upper III-nitride layer,a gate electrode between the source electrode and the drain electrode,second dielectric areas on the upper III-nitride layer, wherein the second dielectric areas are disposed between the source electrode and the gate electrode and between the gate electrode and the drain electrode, anda second layer of doped III-nitride material between the gate electrode and the upper III-nitride layer, wherein the first and second layers of doped III-nitride material in the Schottky diode and in the HEMT, respectively, have different thicknesses.