Multifunctional integrated acoustic devices and systems using epitaxial materials

Patent metadata

Field	Value
Publication number	US-11831295-B2
Application number	US-202017019611-A
Country	US
Kind code	B2
Filing date	Sep 14, 2020
Priority date	Sep 20, 2019
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

Acoustic wave devices based on epitaxially grown heterostructures comprising appropriate combinations of epitaxially grown metallic transition metal nitride (TMN) layers, epitaxially grown Group III-nitride (III-N) piezoelectric semiconductor thin film layers, and epitaxially grown perovskite oxide (PO) layers. The devices can include bulk acoustic wave (BAW) devices, surface acoustic wave (SAW) devices, high overtone bulk acoustic resonator (HBAR) devices, and composite devices comprising HBAR devices integrated with high-electron-mobility transistors (HEMTs).

First claim

What is claimed is:

1. An acoustic wave device, comprising:
a low-acoustic-loss substrate;
a bottom electrode comprising a first epitaxial transition metal nitride (TMN) layer;
a top electrode comprising a second epitaxial TMN layer; and
at least one intermediate layer disposed between the first and second epitaxial TMN layers, the at least one intermediate layer comprising a SrCaTiO 3 perovskite oxide (PO) layer.

2. The acoustic wave device according to claim 1 , wherein the first and second TMN layers comprise NbN x or TaN x .

3. The acoustic wave device according to claim 1 , wherein the second TMN layer is patterned to form an interdigitated transducer (IDT) such that the acoustic wave device forms a surface acoustic wave (SAW) device.

4. A high overtone bulk acoustic resonator (HBAR) device, comprising:
a low-acoustic-loss substrate;
a bottom electrode comprising an epitaxial transition metal nitride (TMN) layer;
a top metal electrode;
an epitaxial III-Nitride (III-N) piezoelectric layer disposed between the top and bottom electrodes; and
an AIN layer disposed between the bottom electrode and the III-N piezoelectric layer.

5. The HBAR device according to claim 4 , wherein the bottom electrode comprises NbN x .

6. The HBAR device according to claim 4 , wherein the top electrode comprises aluminum (Al).

7. The HBAR device according to claim 4 , wherein the III-N piezoelectric layer comprises GaN.

8. The HBAR device according to claim 4 , wherein the AIN layer disposed between the bottom electrode and the III-N piezoelectric layer comprises ScAlN.

9. An integrated HEMT+HBAR acoustic device comprising a high-electron-mobility transistor (HEMT) having a high overtone bulk acoustic resonator (HBAR) integrated therewith;
wherein the HBAR comprises:
a low-acoustic-loss substrate;
a bottom metal electrode comprising an epitaxial transition metal nitride (TMN) layer;
a top metal electrode;
an epitaxial III-Nitride (III-N) piezoelectric layer between the top and bottom metal electrodes; and
an AIN layer disposed between the bottom metal electrode and the III-N piezoelectric layer.

10. The integrated HEMT+HBAR acoustic device according to claim 9 , wherein the bottom electrode comprises NbNx.

11. The integrated HEMT+HBAR acoustic device according to claim 9 , wherein the top metal electrode comprises aluminum (Al).

12. The integrated HEMT+HBAR acoustic device according to claim 9 , wherein the III-N piezoelectric layer comprises GaN.

13. The integrated HEMT+HBAR acoustic device according to claim 9 , wherein the AIN layer disposed between the bottom electrode and the III-N piezoelectric layer comprises ScAlN.

Assignees

• Us Gov Sec Navy

Inventors

• Gokhale Vikrant J
• Downey Brian P
• Hardy Matthew T
• Jin Eric N
• Nepal Neeraj
• Katzer D Scott
• Meyer David J

Classifications

• H03H9/02574 Primary

  of combined substrates, multilayered substrates, piezoelectrical layers on not-piezoelectrical substrate · CPC title

• H03H9/02015

  Characteristics of piezoelectric layers, e.g. cutting angles · CPC title

• H03H9/02976

  with semiconductor devices · CPC title

• H03H9/2426

  in combination with other electronic elements · CPC title

• H03H9/02078

  the vibration mode being overmoded · CPC title