US 12,457,763 B2
III-nitride power semiconductor based heterojunction diode
Florin Udrea, Cambridge (GB); Martin Arnold, Cambridge (GB); Loizos Efthymiou, Cambridge (GB); Giorgia Longobardi, Cambridge (GB); and Sheung Wai Fung, Cambridge (GB)
Assigned to CAMBRIDGE GAN DEVICES LIMITED, Cambridge (GB)
Filed by Cambridge GaN Devices Limited, Cambridge (GB)
Filed on Jan. 31, 2022, as Appl. No. 17/589,735.
Prior Publication US 2023/0246098 A1, Aug. 3, 2023
Int. Cl. H10D 30/47 (2025.01); H10D 62/17 (2025.01); H10D 62/85 (2025.01); H10D 84/80 (2025.01)
CPC H10D 30/47 (2025.01) [H10D 62/364 (2025.01); H10D 62/8503 (2025.01); H10D 84/811 (2025.01)] 18 Claims
OG exemplary drawing
 
1. A III-nitride power semiconductor based heterojunction diode comprising a first terminal and a second terminal and further comprising a substrate and an active device formed on the substrate, the active device comprising:
a III-nitride semiconductor region comprising a heterojunction comprising an active two-dimensional carrier gas;
a source terminal operatively connected to the III-nitride semiconductor region and further connected to the first terminal;
a drain terminal laterally spaced from the first terminal and operatively connected to the III-nitride semiconductor region and further connected to the second terminal;
an active gate region formed over the III-nitride semiconductor region and between the first terminal and the second terminal; and
an internal gate terminal operatively connected to the active gate region;
the III-nitride power semiconductor based heterojunction diode further comprising a sensing device, the sensing device comprising:
a sensing device source terminal; and
a sensing device drain terminal;
wherein an area of the sensing device is smaller than an area of the active device by a factor of at least 5;
the III-nitride power semiconductor based heterojunction diode further comprising:
a sensing load, the sensing load comprising a first sensing load terminal and a second sensing load terminal;
wherein the first sensing load terminal is connected to the first terminal;
wherein the sensing device source terminal is connected to the second sensing load terminal; and
wherein the sensing device drain terminal is connected to the drain terminal of the active device;
wherein the III-nitride semiconductor based heterojunction diode further comprises an output;
wherein the output is configured to output a sensing signal corresponding to a current through the sensing device and/or a voltage drop across the sensing load;
wherein the sensing signal is indicative of a current flowing between the first terminal and the second terminal when a bias is applied between the first terminal and the second terminal;
wherein the III-nitride power semiconductor based heterojunction diode further comprises a feedback circuit connected between the sensing load and the internal gate terminal;
wherein the feedback circuit comprises:
a first feedback circuit terminal;
a second feedback circuit terminal;
a third feedback circuit terminal; and
a fourth feedback circuit terminal;
wherein the first feedback circuit terminal is connected to the first sensing load terminal; wherein the second feedback circuit terminal is connected to the second sensing load terminal; and wherein the third feedback circuit terminal is connected to the internal gate terminal;
wherein the feedback circuit further comprises:
at least one inverter stage comprising at least one transistor, wherein the at least one transistor comprises:
a transistor drain terminal;
a transistor gate terminal; and
a transistor source terminal;
wherein the transistor source terminal is connected to the first feedback circuit terminal, the transistor gate terminal is operatively connected to the second feedback circuit terminal, the transistor drain terminal is connected to the third feedback circuit terminal and the internal gate terminal; and the transistor drain terminal is further operatively connected to a potential via the fourth feedback circuit terminal;
wherein the feedback circuit is configured to detect a forward current through the sensing device and/or a positive voltage drop across the sensing load; and
wherein the feedback circuit is further configured to provide a potential to the internal gate terminal upon detection of the forward current through the sensing device and/or the positive voltage drop across the sensing load, wherein the potential provided to the internal gate terminal is greater than the potential at the first terminal.