Method for processing a plurality of micro-machined mirror assemblies

• US 6,200,882 B1
• Filed: 11/13/1998
• Issued: 03/13/2001
• Est. Priority Date: 06/10/1998
• Status: Expired due to Fees

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology plc (Seagate Technology Holdings Plc)
• Inventors: Jackson, Kathy J., Jerman, John H., Drake, Joseph D.
• Primary Examiner(s): Niebling, John F.
• Assistant Examiner(s): ZARNEKE, DAVID A
• Application Number:
  US09/191,502
• Time in Patent Office: 851 Days
• Field of Search: 438/3, 438/52, 438/53, 438/460, 438/464, 438/465, 216/22, 216/24, 216/26
• US Class Current: 438/464
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G02B 26/0816 by means of one or more reflecting elements
• CPC Class Codes: G11B 11/10554 the transducers being disposed on the same side of the carrier flying heads G11B11/1058
• CPC Class Codes: G11B 11/10576 with provision for moving the transducers for maintaining alignment or spacing relative to the carrier
• CPC Class Codes: G11B 11/1058 Flying heads
• CPC Class Codes: G11B 7/08564 using galvanomirrors
• CPC Class Codes: G11B 7/22 Apparatus or processes for the manufacture of optical heads, e.g. assembly

Abstract

A method for processing a plurality of mirror assemblies formed together from a silicon wafer. The method includes the steps of exposing the mirror assemblies to an acid release etch to produce released mirror assemblies and rinsing the released mirror assemblies to produce washed mirror assemblies. The washed mirror assemblies are dried to produce dried mirror assemblies and the dried mirror assemblies are mounted onto a mounting tape to produce mounted mirror assemblies. The mounted mirror assemblies are diced or scribed to produce a plurality of separated mirror assemblies, which are separated from the mounting tape so as to produce a plurality of discrete mirror assemblies.

Claims

1. A method for processing a plurality of mirror assemblies formed together from a silicon wafer having at least one layer of a dielectric material disposed thereon, each of the mirror assemblies being of micron dimensions and for use in a magneto-optical data storage system and having a planar mirror which is spaced apart from the at least one dielectric layer and disposed generally parallel to the at least one dielectric layer, the planar mirror having first and second end portions and a longitudinal axis extending between the first and second end portions, at least a portion of the mirror being of a conductive material, each of the mirror assemblies having first and second hinge members extending along the longitudinal axis and connected to the first and second end portions and means for securing the first and second hinge members to the at least one dielectric layer for permitting the mirror to rock between first and second positions about the longitudinal axis relative to the at least one dielectric layer when operational, each of the mirror assemblies having first and second spaced-apart electrodes carried by the at least one dielectric layer for driving the mirror between the first and second positions during operation, the method comprising the steps of exposing the mirror assemblies to an acid release etch to release the mirror relative to the at least one dielectric layer and thus produce released mirror assemblies, rinsing the released mirror assemblies to produce washed mirror assemblies, drying the washed mirror assemblies to produce dried mirror assemblies, coating the dried mirror assemblies with an organic protectant to produce coated mirror assemblies, mounting the coated mirror assemblies on a mounting tape to produce mounted mirror assemblies, dicing the mounted mirror assemblies to produce a plurality of diced mirror assemblies, removing the organic protectant from the diced mirror assemblies to produce cleaned mirror assemblies and separating the cleaned mirror assemblies from the mounting tape so as to produce discrete mirror assemblies.

2. The method of claim 1 wherein the organic protectant is a photoresist and wherein the removing step includes the step of removing the photoresist with a solvent.

3. The method of claim 2 wherein the solvent is acetone and wherein the removing step includes the step of washing the acetone from the diced mirror assemblies with isopropanol.

4. The method of claim 2 wherein the coating step includes the step of coating the dried mirror assemblies with photoresist number AZ1813 sold by Hoechst Celanese of Dallas, Tex.

5. The method of claim 1 wherein the organic protectant is a photoresist and wherein the removing step includes the step of removing the photoresist by means of a plasma etch.

6. The method of claim 1 wherein the mounting tape is a heat release tape.

7. The method of claim 6 wherein the separating step includes heating the cleaned mirror assemblies to 100°

C. to release the cleaned mirror assemblies from the heat release tape.

8. The method of claim 1 wherein the mounting tape is Revalpha Tape No. 3195 sold by Nitto Denko of Osaka, Japan.

9. The method of claim 1 wherein the mounting tape is Revalpha Tape No. 3198 sold by Nitto Denko of Osaka, Japan.

10. The method of claim 1 wherein the dicing step includes the step of dicing the mounted mirror assemblies with a semiconductor industry dicing saw.

11. The method of claim 1 further comprising the step of sorting the discrete mirror assemblies and placing the discrete mirror assemblies in a tray.

12. The method of claim 1 wherein the drying step includes drying the washed mirror assemblies with a nitrogen gun and then in an oven at 90°

C. for a time period ranging from 5 to 10 minutes.

13. A method for processing a plurality of mirror assemblies formed together from a silicon wafer having at least one layer of a dielectric material disposed thereon, each of the mirror assemblies being of micron dimensions and for use in a magneto-optical data storage system and having a planar mirror which is spaced apart from the at least one dielectric layer and disposed generally parallel to the at least one dielectric layer, the planar mirror having first and second end portions and a longitudinal axis extending between the first and second end portions, at least a portion of the mirror being of a conductive material, each of the mirror assemblies having first and second hinge members extending along the longitudinal axis and connected to the first and second end portions and means for securing the first and second hinge members to the at least one dielectric layer for permitting the mirror to rock between first and second positions about the longitudinal axis relative to the at least one dielectric layer when operational, each of the mirror assemblies having first and second spaced-apart electrodes carried by the at least one dielectric layer for driving the mirror between the first and second positions during operation, the method comprising the steps of coating the mirror assemblies with an organic protectant to produce coated mirror assemblies, mounting the coated mirror assemblies on a mounting tape to produce mounted mirror assemblies, dicing the mounted mirror assemblies to produce a plurality of diced mirror assemblies, removing the organic protectant from the diced mirror assemblies to produce cleaned mirror assemblies, exposing the cleaned mirror assemblies to an acid release etch to produce released mirror assemblies, rinsing the released mirror assemblies to produce washed mirror assemblies, drying the washed mirror assemblies to produce dried mirror assemblies and separating the dried mirror assemblies from the mounting tape so as to produce discrete mirror assemblies.

14. The method of claim 13 wherein the dicing step includes the step of dicing the mounted mirror assemblies with a semiconductor industry dicing saw.

15. The method of claim 13 wherein the drying step includes drying the washed mirror assemblies with a nitrogen gun and then in an oven at 90°

C. for a time period ranging from 5 to 10 minutes.

16. The method of claim 13 wherein the mounting tape is a heat release tape and wherein the separating step includes heating the dried mirror assemblies to 100°

C. to release the dried mirror assemblies from the heat release tape.

17. The method of claim 13 further comprising the step of coating the released mirror assemblies with a self-assembled monolayer coating prior to the rinsing step.

18. The method of claim 13 wherein the organic protectant is a photoresist.

19. A method for processing a plurality of mirror assemblies formed together from a silicon wafer having at least one layer of a dielectric material disposed thereon, each of the mirror assemblies being of micron dimensions and for use in a magneto-optical data storage system and having a planar mirror which is spaced apart from the at least one dielectric layer and disposed generally parallel to the at least one dielectric layer, the planar mirror having first and second end portions and a longitudinal axis extending between the first and second end portions, at least a portion of the mirror being of a conductive material, each of the mirror assemblies having first and second hinge members extending along the longitudinal axis and connected to the first and second end portions and means for securing the first and second hinge members to the at least one dielectric layer for permitting the mirror to rock between first and second positions about the longitudinal axis relative to the at least one dielectric layer when operational, each of the mirror assemblies having first and second spaced-apart electrodes carried by the at least one dielectric layer for driving the mirror between the first and second positions during operation, the method comprising the steps of exposing the mirror assemblies to an acid release etch to produce released mirror assemblies, rinsing the released mirror assemblies to produce washed mirror assemblies, drying the washed mirror assemblies to produce dried mirror assemblies, mounting the dried mirror assemblies onto a mounting tape to produce mounted mirror assemblies, scribing and breaking the mounted mirror assemblies to produce a plurality of scribed mirror assemblies and separating the scribed mirror assemblies from the mounting tape so as to produce discrete mirror assemblies.

20. The method of claim 19 wherein the acid is hydrofluoric acid.

21. The method of claim 19 further comprising the step of coating the released mirror assemblies with a self-assembled monolayer coating prior to the rinsing step.

22. The method of claim 19 wherein the mounting tape is a heat release tape.

23. The method of claim 19 wherein the rinsing step includes rinsing the released mirror assemblies in water.