High quality factor embedded resonator wafers

Patent metadata

Field	Value
Publication number	US-11209398-B2
Application number	US-201916597615-A
Country	US
Kind code	B2
Filing date	Oct 9, 2019
Priority date	Sep 13, 2019
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

Embodiments disclosed herein include diagnostic substrates and methods of using such substrates. In an embodiment, a diagnostic substrate comprises a substrate, and a device layer over the substrate. In an embodiment, the diagnostic substrate further comprises a resonator in the device layer. In an embodiment, the resonator comprises a cavity, a cover layer over the cavity, and electrodes within the cavity for driving and sensing resonance of the cover layer. In an embodiment, the diagnostic substrate further comprises a reflector surrounding a perimeter of the resonator.

First claim

What is claimed is:

1. A diagnostic substrate, comprising:
a substrate;
a device layer over the substrate;
a resonator in the device layer, wherein the resonator comprises:
a cavity;
a cover layer over the cavity; and electrodes within the cavity for driving and sensing resonance of the cover layer; and
a reflector surrounding a perimeter of the resonator, wherein the reflector is configured to be modulated to reflect different frequencies, wherein modulating the reflector comprises changing a dimension of the cavity, wherein the dimension is changed by an actuator.

2. The diagnostic substrate of claim 1 , wherein the reflector is a quarter-wavelength cavity reflector.

3. The diagnostic substrate of claim 1 , wherein the reflector is embedded in the device layer.

4. The diagnostic substrate of claim 1 , wherein a bottom surface of the cavity and a bottom surface of the reflector are at the same Z-height in the device layer.

5. The diagnostic substrate of claim 1 , wherein the reflector is above a top surface of the device layer.

6. The diagnostic substrate of claim 1 , wherein the reflector is below a bottom surface of the cavity.

7. The diagnostic substrate of claim 1 , further comprising:
a second reflector surrounding a perimeter of the reflector.

8. The diagnostic cavity of claim 1 , wherein modulating the reflector comprises changing a density or a modulus of a material in the reflector.

9. The diagnostic cavity of claim 8 , further comprising:
a heater proximate to the reflector.

10. The diagnostic cavity of claim 1 , wherein the reflector comprises a phase changing material.

11. A diagnostic substrate, comprising:
a substrate;
a device layer over the substrate, wherein the device layer has a first impedance;
a ring having a second impedance, wherein the ring surrounds at least a portion of the device layer, wherein the ring is a cavity into the device layer;
drivers and sensors configured to detect resonance; and
a reflector surrounding the ring, wherein the reflector is configured to be modulated to reflect different frequencies, wherein modulating the reflector comprises changing a dimension of the cavity, wherein the dimension is changed by an actuator.

12. A method for determining a processing parameter, comprising:
processing a diagnostic substrate, wherein the diagnostic substrate comprises a resonator and a reflector surrounding the resonator;
driving the resonator to a plurality of resonance modes, wherein acoustic waves propagating away from the resonator are reflected back towards the resonator by the reflector; recording a resonant frequency of the resonator for each of the resonance modes; and
determining the processing parameter from the resonant frequencies of the plurality of resonance modes.

13. The method of claim 12 , wherein driving the resonator to a plurality of oscillation modes comprises applying a drive signal that is a chirp or a ping.

14. The method of claim 12 , wherein the plurality of resonance modes comprises at least a first resonance mode and a second resonance mode, and wherein the first resonance mode is substantially parallel to a direction of a plurality of trenches over the resonator and the second resonance mode is substantially perpendicular to the plurality of trenches.

15. The method of claim 12 , wherein the resonator is driven to a plurality of resonance modes in-situ in a chamber, in a load lock, in a mobile testing apparatus, or in a non-vacuum environment.

16. A diagnostic substrate, comprising:
a substrate;
a device layer over the substrate;
a resonator in the device layer, wherein the resonator comprises:
a cavity;
a cover layer over the cavity; and electrodes within the cavity for driving and sensing resonance of the cover layer;
a reflector surrounding a perimeter of the resonator, wherein the reflector is configured to be modulated to reflect different frequencies, wherein modulating the reflector comprises changing a density or a modulus of a material in the reflector; and
a heater proximate to the reflector.

Assignees

• Applied Materials Inc

Inventors

• Lin Chuang-Chia
• Kumar Surajit
• Ummethala Upendra

Classifications

• H10P74/277

  Circuits for electrically characterising or monitoring manufacturing processes, e.g. circuits in tested chips or circuits in testing wafers · CPC title

• H10P74/203

  Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects · CPC title

• H10P72/0604 Primary

  Process monitoring, e.g. flow or thickness monitoring · CPC title

• H03H9/2405

  of microelectro-mechanical resonators · CPC title

• H03H9/02566

  of semiconductor substrates · CPC title