Integrated CMOS high precision piezo-electrically driven clock

• US 20030058057A1
• Filed: 09/21/2001
• Published: 03/27/2003
• Est. Priority Date: 09/21/2001
• Status: Active Grant

• Current Assignee: Intellectual Ventures I LLC (Intellectual Ventures LLC)
• Original Assignee: Gallitzin Allegheny LLC (Intellectual Ventures LLC)
• Inventors: Schmidt, Dominik J.
• Granted Patent: US 7,098,748 B2
• Time in Patent Office: Days
• US Class Current: 331/175
• CPC Class Codes: H03L 1/00 Stabilisation of generator output against variations of physical values, e.g. power supply
• CPC Class Codes: H03L 1/025 and a memory for digitally storing correction values
• CPC Class Codes: H03L 1/028 of generators comprising piezoelectric resonators H03L1/021, H03L1/022 take precedence; oscillation generators with a piezoelectric resonator H03B5/32
• CPC Class Codes: H03L 1/04 Constructional details for maintaining temperature constant

Abstract

A clock oscillator embedded in an integrated circuit, including a piezoelectric resonator formed on the integrated circuit; a clock generator coupled to the on-chip piezoelectric resonator, one or more sensors adapted to sense one or more environmental parameters affecting the piezoelectric resonator; and a processor coupled to the clock generator and the one or more sensors to adjust the frequency of the clock generator based on the one or more environmental parameters.

Claims

1. A clock oscillator embedded in an integrated circuit, comprising:

a piezoelectric resonator formed on the integrated circuit;

a clock generator coupled to the piezoelectric resonator;

one or more sensors adapted to sense one or more environmental parameters affecting the piezoelectric resonator; and

a processor coupled to the clock generator and the one or more sensors to adjust the frequency of the clock generator based on the one or more environmental parameters.

2. The oscillator of claim 1, wherein the one or more environmental parameters includes temperature or supply voltage.

3. The oscillator of claim 1, wherein the one or more sensors include a temperature sensor, a hot electron sensor, and a shock sensor.

4. The oscillator of claim 1, wherein the one or more sensors include one or more temperature sensors.

5. The oscillator of claim 1, wherein the piezoelectric resonator comprises an integrated piezo-electric film.

6. The oscillator of claim 1, wherein the piezoelectric resonator comprises an integrated ZnO film.

7. The oscillator of claim 1, further comprising a doped polysilicon cantilever deposited over a pit etched with tetramethyl-ammonium hydride (TMAH).

8. The oscillator of claim 7, further comprising a polysilicon layer deposited and patterned and a boron layer implanted into the polysilicon layer, wherein the polysilicon layer is undercut using TMAH.

9. The oscillator of claim 1, wherein a portion of the integrated circuit is heavily implanted.

10. The oscillator of claim 9, wherein the implanted portion oscillates

11. The oscillator of claim 9, wherein the integrated circuit comprises an epitaxial portion with a lightly doped surface.

12. The oscillator of claim 11, further comprising a heavily doped section surrounding the epitaxial portion.

13. The oscillator of claim 12, wherein the doped section is doped with boron.

14. The oscillator of claim 12, wherein the doped section comprises a piezo-electric crystal.