Hard disk driver with an integrated structure for electrostatically removing dielectric particles generated during the operation, and electrostatic cleaning method for a hard disk driver

• US 6,496,997 B1
• Filed: 07/20/1999
• Issued: 12/24/2002
• Est. Priority Date: 07/22/1998
• Status: Expired due to Term

• Current Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Murari, Bruno, Ferrari, Paolo, Vigna, Benedetto
• Primary Examiner(s): Markoff, Alexander
• Application Number:
  US09/357,441
• Time in Patent Office: 1,253 Days
• Field of Search: 209/128, 209/129, 209/130, 15/15.1, 134/1
• US Class Current: 15/1.51
• CPC Class Codes: G11B 21/02 Driving or moving of heads
• CPC Class Codes: H02N 1/004 in which a body is moved along a path due to interaction with an electric field travelling along the path

Abstract

An electrostatic cleaning structure of a hard disk driver is formed by a plurality of concentric conductive regions to which biasing pulse trains are supplied. Each biased conductive region generates an electric field attracting any dielectric particle. The pulse trains supplied to immediately adjacent conductive regions are phase-shifted by a predetermined time and in a direction linked to a desired direction of removal for the electrostatic particles. Voltage pulses sent to each conductive region are delayed with respect to voltage pulses sent to an immediately preceding conductive region in the direction of desired removal, and are advanced with respect the voltage pulses sent to an immediately successive conductive region.

Claims

1. A hard disk driver, comprising:

an electrostatic cleaning structure for dielectric particles, wherein said electrostatic cleaning structure comprises at least three conductive regions disposed adjacent to each other;

a sequencing and periodic biasing circuit for said conductive regions to bias said conductive regions according to a sequence that produces removal of the dielectric particles in a desired direction; and

a substrate of semiconductor material and an electrically insulating material layer extending on said substrate, wherein said conductive regions extend on said electrically insulating material layer.

2. The driver according to claim 1 wherein said sequencing and periodic biasing circuit comprises a pulsed voltage source and connection lines connected to said conductive regions to supply successive voltage pulses to conductive regions adjacent in said direction of desired removal.

3. The driver according to claim 2 wherein said pulsed voltage source has n outputs each connected to a respective connection line, wherein each connection line is connected to a conductive region of every nth conductive region and wherein different connection lines are connected to adjacent conductive regions.

4. The driver according to claim 3 wherein n is equal to three.

5. The driver according to claim 1 wherein said conductive regions extend along concentric closed lines.

6. The driver according to claim 1 wherein said conductive regions extend along concentric circumferences.

7. The driver according to claim 1, further comprising connection lines connected to said conductive regions to supply successive voltage pulses to conductive regions adjacent in said direction of desired removal, and wherein said conductive regions comprise metal of a first metal level, wherein said connection lines comprise metal of a second metal level, and further comprising a dielectric material layer extending between said conductive regions and said connection lines, wherein said dielectric material layer has contact openings between said conductive regions and said connection lines.

8. The hard disk driver of claim 1 wherein the electrostatic cleaning structure is formed adjacent to a microactuator of a read/write head.

9. The hard disk driver of claim 8 wherein the electrostatic cleaning structure is formed around the microactuator.

10. A system operable to remove a particle generated during read/write actuation of a hard disk, the system comprising:

a microactuator to actuate the hard disk;

an integrated device operatively positioned adjacent to the miroactuator, wherein the integrated device has a substrate of semiconductor material, an electrically insulating material layer extending on said substrate, and an electrostatic cleaning structure and wherein the cleaning structure has at least three conductive regions disposed adjacent to each other, wherein said conductive regions extend on said electrically insulating material layer; and

a sequencing and biasing element connected to the plurality of conductive regions to bias the plurality of conductive regions, wherein the plurality of conductive regions are biased according to a sequence corresponding to a desired direction of removal of the particle, and wherein the biased conductive regions apply forces to the particle to move the particle in the desired direction.

11. The system of claim 10 wherein the sequencing and biasing element comprises a voltage source and a plurality of connection lines connecting the conductive regions to the voltage source, wherein the voltage source supplies successive voltage pulses through the connection lines to successive conductive regions, and wherein the voltage pulses are supplied by the voltage source in the sequence corresponding to the desired direction of removal of the particle.

12. The system of claim 10 wherein the conductive regions extend along concentric closed lines substantially surrounding the microactuator.

13. The system of claim 10 wherein the sequencing and biasing element is integrated with the integrated device.

14. A hard disk driver, comprising:

an electrostatic cleaning structure for dielectric particles, wherein said electrostatic cleaning structure comprises at least three conductive regions disposed adjacent to each other;

a sequencing and periodic biasing circuit for said conductive regions to bias said conductive regions according to a sequence corresponding to a direction of desired removal of the dielectric particles;

a substrate of semiconductor material and an electrically insulating material layer extending on said substrate, wherein said conductive regions extend on said electrically insulating material layer; and

a pulsed voltage source and connection lines connected to said conductive regions to supply successive voltage pulses to conductive regions adjacent in said direction of desired removal.

15. The driver according to claim 14 wherein said conductive regions comprise metal of a first metal level, wherein said connection lines comprise metal of a second metal level, and further comprising a dielectric material layer extending between said conductive regions and said connection lines, wherein said dielectric material layer has contact openings between said conductive regions and said connection lines.