Deposition method of a metallic layer on a substrate of a resonator device

Patent metadata

Field	Value
Publication number	US-12043891-B2
Application number	US-202117196999-A
Country	US
Kind code	B2
Filing date	Mar 9, 2021
Priority date	Apr 9, 2020
Publication date	Jul 23, 2024
Grant date	Jul 23, 2024

Abstract

Sputter depositing a metallic layer on a substrate in the fabrication of a resonator device includes providing a magnetron sputtering apparatus comprising a chamber, a substrate support disposed within the chamber, a target made from a metallic material, and a plasma generating device, wherein the substrate support and the target are separated by a distance of 10 cm or less; supporting the substrate on the substrate support; performing a DC magnetron sputtering step that comprises sputtering the metallic material from the target onto the substrate so as to form a metallic layer on the substrate, wherein during the DC magnetron sputtering step the chamber has a pressure of at least 6 mTorr of a noble gas, the target is supplied with a power having a power density of at least 6 W/cm 2 , and the substrate has a temperature in the range of 200-600° C.

First claim

What is claimed is:

1. A method of sputter depositing a metallic layer on a substrate in the fabrication of a resonator device, the method comprising the steps of:
providing a magnetron sputtering apparatus comprising a chamber, a substrate support disposed within the chamber, a target made from a metallic material, and a plasma generating device, wherein the substrate support and the target are separated by a distance of 10 cm or less;
supporting the substrate on the substrate support; and
performing a DC magnetron sputtering step that comprises sputtering the metallic material from the target onto the substrate so as to form a metallic layer on the substrate, wherein the metallic layer is composed of a metal selected from molybdenum (Mo), tungsten (W), titanium (Ti), tantalum (Ta), platinum (Pt) or ruthenium (Ru), and wherein during the DC magnetron sputtering step the chamber has a pressure of at least 6 mTorr of a noble gas, the target is supplied with a power having a power density of at least 6 W/cm 2 , and the substrate has a temperature in the range of 200-600° C.

2. The method according to claim 1 , wherein the substrate is a silicon substrate.

3. The method according to claim 1 , wherein the power density is at least 8 W/cm 2 .

4. The method according to claim 1 , wherein the power density is less than about 24 W/cm 2 .

5. The method according to claim 1 , wherein during the DC magnetron sputtering step the chamber has a pressure of at least 7 mTorr.

6. The method according to claim 1 , wherein during the DC magnetron sputtering step the chamber has a pressure of about 20 m Torr or less.

7. The method according to claim 1 , wherein the DC magnetron sputtering step is performed at a temperature in the range of 300-500° C.

8. The method according to claim 1 , wherein during the DC magnetron sputtering step, a bias power is supplied to the substrate support.

9. The method according to claim 8 , wherein the bias power is an RF bias power.

10. The method according to claim 8 , wherein the bias power has a power in the range of 10-600 W.

11. The method according to claim 1 , wherein the DC magnetron sputtering step comprises sputtering the metallic material from the target using a plasma formed from the noble gas, and wherein the noble gas is argon (Ar), krypton (Kr), xenon (Xe), or a mixture thereof.

12. The method according to claim 1 , wherein the metallic layer has a thickness of about 300 nm or less.

13. The method according to claim 1 , wherein the distance is about 75 mm or less.

14. The method according to claim 1 , wherein the resonator device is an acoustic wave device.

15. A method of fabricating a resonator device comprising the steps of:
(a) providing a substrate;
(b) depositing a first metallic layer onto the substrate;
(c) depositing a piezoelectric layer onto the first metallic layer; and
(d) depositing a second metallic layer onto the piezoelectric layer, wherein at least step (b) or step (d) is performed using the method according to claim 1 .

16. A substrate comprising a molybdenum layer deposited using the method according to claim 1 , wherein the molybdenum layer has a resistivity of less than about 10 μΩ·cm.

17. A resonator device comprising a molybdenum layer deposited using the method according to claim 1 , wherein the molybdenum layer has a resistivity of less than about 10 μΩ·cm.

18. A resonator device according to claim 17 , wherein the resonator device is an acoustic wave device.

Assignees

• Spts Technologies Ltd

Inventors

• Haymore Scott
• Thomas Adrian
• Burgess Steve

Classifications

• H03H9/02614

  Treatment of substrates, e.g. curved, spherical, cylindrical substrates ensuring closed round-about circuits for the acoustical waves · CPC title

• H03H9/02574

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

• H03H9/02047

  Treatment of substrates · CPC title

• H03H3/08

  for the manufacture of resonators or networks using surface acoustic waves · CPC title

• C23C14/351

  using a magnetic field in close vicinity to the substrate · CPC title