IP Library › Granted Patent US 12,557,321
Granted Patent B2
US 12,557,321 · App. 17/666,671 · Granted Feb 17, 2026

Rare-earth III-nitride N-polar HEMT

Inventors: John Andrew Logan (Lawrence, MA); Brian Douglas Schultz (Lexington, MA); Maher Bishara Tahhan (Tewksbury, MA)
Assignee: RAYTHEON COMPANY
H10D30/472H10D62/8503
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Quick Facts
Patent No.
US 12,557,321
App. No.
17/666,671
Granted
Feb 17, 2026
Kind
B2
Abstract

A high electron mobility transistor (HEMT) heterostructure includes a substrate; a N-polar channel layer; and a N-polar barrier layer positioned between the substrate and the channel layer, wherein the barrier layer comprises a rare-earth III-nitride material. The rare earth III-nitride material can be ScAlN.

Claims (18)

1 . A heterostructure, comprising:

a substrate;

a N-polar channel layer; and

a N-polar barrier layer positioned between the substrate and the channel layer, wherein the barrier layer comprises a rare-earth III-nitride material, and wherein the rare-earth III-nitride material is in an N-polar orientation.

2 . The heterostructure of claim 1 , wherein the rare earth III-nitride material is selected from the group consisting of ScAlN, YAlN, LaAlN, PrAlN, GdAlN, ErAlN and combinations thereof.

3 . The heterostructure of claim 1 , wherein the rare earth III-nitride material is selected from the group consisting of ScAlN, YAlN and combinations thereof.

4 . The heterostructure of claim 1 , further comprising at least one of a nucleation layer, a buffer layer, and a charge mitigation transition layer between the substrate and the barrier layer.

5 . The heterostructure of claim 1 , further comprising a nucleation layer between the substrate and the barrier layer.

6 . The heterostructure of claim 5 , wherein the nucleation layer comprises an AlN nucleation layer.

7 . The heterostructure of claim 5 , further comprising a buffer layer between the nucleation layer and the barrier layer.

8 . The heterostructure of claim 7 , wherein the buffer layer comprises a GaN buffer layer.

9 . The heterostructure of claim 7 , further comprising a charge mitigation transition layer between the buffer layer and the barrier layer.

10 . The heterostructure of claim 9 , wherein the charge mitigation transition layer comprises a compositionally graded rare-earth III-nitride alloy layer.

11 . The heterostructure of claim 9 , wherein the charge mitigation transition layer comprises a doped GaN layer.

12 . The heterostructure of claim 1 , further comprising at least one capping layer disposed opposite from the barrier layer relative to the channel layer.

13 . The heterostructure of claim 12 , wherein the at least one capping layer is selected from the group consisting of an etch stop layer, an interlayer, an upper barrier and combinations thereof.

14 . The heterostructure of claim 1 , wherein the channel layer comprises a GaN channel layer.

15 . The heterostructure of claim 7 , wherein the buffer layer is in an N-polar orientation.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 8, 2022
From: TAHHAN, MAHER BISHARA; LOGAN, JOHN ANDREW; SCHULTZ, BRIAN DOUGLAS
To: RAYTHEON COMPANY
Reel/Frame 058920/0191 →
Continuity (2)
Provisional Application 63148794 · Feb 12, 2021
Related Publication 20220262937A1 · Aug 18, 2022
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