Bellows driven air floatation abrading workholder

• US 8,845,394 B2
• Filed: 10/29/2012
• Issued: 09/30/2014
• Est. Priority Date: 10/29/2012
• Status: Expired due to Fees

• Current Assignee: Wayne O. Duescher
• Original Assignee: Wayne O. Duescher
• Inventors: Duescher, Wayne O.
• Primary Examiner(s): NGUYEN, GEORGE BINH MINH
• Application Number:
  US13/662,863
• Publication Number:
  US 20140120804A1
• Time in Patent Office: 701 Days
• Field of Search: 451/41, 451285-290, 451397-398
• US Class Current: 451/41
• CPC Class Codes: B24B 37/30 for single side lapping of plane surfaces

Abstract

Flat-surfaced workpieces such as semiconductor wafers are attached to a rotatable floating workpiece holder carrier rotor that is supported by and rotationally driven by a bellows. The wafer carrier rotor is contained by a set of idlers that are attached to a stationary rotor housing to provide support against abrading forces that are imposed on the wafer by the moving abrasive coating on a rotary platen. The idlers allow low-friction operation of the abrading system to be provided at the very high abrading speeds used in high speed flat lapping with raised-island abrasive disks. The system is also well suited for lapping optical devices and rotary seals and for chemical mechanical planarization (CMP) polishing of wafers using resilient pads. Pressurized air is injected into the bellows device to provide uniform abrading pressure across the full surface of the wafer. Wafers can be attached to the workpiece carrier with vacuum.

Claims

1. An abrading machine workpiece substrate carrier apparatus comprising:

a) a movable, nominally-horizontal, stationary-positioned carrier housing having an outer periphery and an outer periphery area that is nominally-horizontal and is adjacent to the stationary-positioned carrier housing outer periphery, the carrier housing having rotary bearings that support a vertical hollow rotatable carrier drive shaft having i) a carrier drive shaft cross-section, ii) a carrier drive shaft length and iii) a carrier drive shaft axis of rotation that is concentric to the carrier drive shaft cross-section and extends along a length of the carrier drive shaft wherein the carrier drive shaft is fixed vertically to the stationary-positioned carrier housing and wherein the stationary-positioned carrier housing is moveable in a vertical direction;

b) a circular rotatable drive plate having a rotatable drive plate outer diameter, a rotatable drive plate top surface and an opposed rotatable drive plate bottom surface wherein both the rotatable drive plate top surface and the rotatable drive plate bottom surface are nominally horizontal and wherein the rotatable drive plate has a rotation axis that is perpendicular to the rotatable drive plate top surface and is located at the center of the rotatable drive plate top surface, wherein the rotatable drive plate top surface is attached to and is supported by the carrier drive shaft and wherein the carrier drive shaft axis of rotation is concentric with the rotatable drive plate rotation axis;

c) a rotatable bellows spring device having multiple annular rings of flat-surfaced metal or polymers having annular ring outer diameters and annular ring inside diameters where adjacent annular rings are joined together at their outer diameters and adjacent annular rings are joined together at their inner diameters to form the rotatable bellows spring device wherein the multiple individual annular rings are nominally horizontal and where the individual annular rings are flexible in a vertical direction and where the rotatable bellows spring device has a rotatable bellows spring device top annular ring and a rotatable bellows spring device bottom annular ring and where the rotatable bellows spring device has a nominally-vertical axis of rotation that is perpendicular to the rotatable bellows spring device nominally-horizontal top annular ring and the rotatable bellows spring device axis of rotation is located at the center of the rotatable bellows spring device top annular ring wherein the rotatable bellows spring device can flex in a vertical direction;

d) wherein the rotatable bellows spring device individual annular ring outer diameters are approximately the same and wherein the rotatable bellows spring device individual annular ring outer diameters are approximately the same as the rotatable drive plate outer diameter wherein the rotatable bellows spring device top annular ring is attached to the rotatable drive plate bottom surface and wherein the rotatable bellows spring device axis of rotation is nominally-coincident with the rotatable drive plate rotation axis;

e) a circular rotatable workpiece carrier plate having a rotatable workpiece carrier plate top surface and an opposed rotatable workpiece carrier plate flat bottom surface wherein both the rotatable workpiece carrier plate top surface and the rotatable workpiece carrier plate bottom surface are nominally horizontal and wherein the rotatable workpiece carrier plate has a rotation axis that is perpendicular to the rotatable workpiece carrier plate top surface and is located at the center of the rotatable workpiece carrier plate top surface, wherein the rotatable workpiece carrier plate has a rotatable workpiece carrier plate outer diameter that is approximately the same as outer diameters of the rotatable bellows spring device individual annular ring wherein the rotatable workpiece carrier plate has a rotatable workpiece carrier plate thickness and a rotatable workpiece carrier plate outer periphery surface located at the rotatable workpiece carrier plate outer diameter and extends from the rotatable workpiece carrier plate top surface to the rotatable workpiece carrier plate flat bottom surface;

f) the rotatable bellows spring device bottom annular ring is attached to the rotatable workpiece carrier plate top surface and wherein the rotatable bellows spring device axis of rotation is nominally-coincident with the rotatable workpiece carrier plate rotation axis;

g) at least two roller idlers having respective stationary nominally-vertical roller idler shafts having respective stationary roller idler shaft lengths attached to the stationary-positioned carrier housing outer periphery in the stationary-positioned carrier housing outer periphery area, wherein the respective at least two stationary roller idler shafts support respective roller idler bearings that support respective rotatable roller idler shells, and wherein the respective rotatable roller idler outer shells have a roller idler outer shell periphery and a roller idler outer shell periphery surface area that is nominally-vertical and the respective rotatable roller idler outer shells rotate about a rotation axis that is concentric with the roller idler shafts and extend along the respective roller idler shafts lengths, wherein the respective rotation axes of the respective roller idler shafts are nominally-vertical;

h) the at least two multiple roller idlers are attached to the stationary-positioned carrier housing outer periphery area around the stationary-positioned carrier housing outer periphery, the at least two respective rotatable roller idler outer shells periphery surface areas are positioned in contact with the rotatable workpiece carrier plate outer diameter rotatable workpiece carrier plate outer periphery surface, and the at least two multiple roller idlers care in rolling contact with the rotatable workpiece carrier plate outer periphery surface as the rotatable workpiece carrier plate is rotated and the at least two multiple roller idlers maintain the rotatable workpiece carrier plate rotation axis to be concentric with the carrier drive shaft axis of rotation when the rotatable workpiece carrier plate is rotated;

i) wherein at least one workpiece having parallel opposed flat workpiece top surfaces and flat workpiece bottom surfaces are attached to the rotatable workpiece carrier plate flat bottom surface and wherein the at least one workpiece top surface is attached to the rotatable workpiece carrier plate flat bottom surface;

j) a rotatable abrading platen having a flat abrasive coated abrading surface that is nominally horizontal;

k) wherein the stationary-positioned carrier housing is moveable vertically to position the flat workpiece bottom surface into flat-surfaced abrading contact with the rotatable abrading platen abrading surface and the stationary-positioned carrier housing is moveable vertically to move the flat workpiece bottom surface from flat-surfaced abrading contact with the rotatable abrading platen abrading surface.

2. The apparatus of claim 1 where the rotatable bellows spring device top annular ring is attached to the rotatable drive plate bottom surface and the spring device bottom annular ring is attached to the rotatable workpiece carrier plate top surface, wherein a sealed enclosed pressure chamber is formed in an internal volume that is contained by the rotatable bellows spring device, the rotatable drive plate bottom surface and the rotatable workpiece carrier plate top surface, wherein the rotatable bellows spring device, the rotatable drive plate bottom surface, the rotatable workpiece carrier plate top surface and the rotatable bellows spring device multiple individual annular ring joints are pressure and vacuum sealed, wherein the rotatable drive is attached to the rotatable drive plate bottom surface and the rotatable bellows plate bottom surface is pressure and vacuum sealed and where the rotatable workpiece carrier plate top surface is pressure and vacuum sealed, wherein controlled-pressure air or controlled-pressure fluid or controlled-pressure vacuum can be introduced into the sealed enclosed pressure chamber through a fluid passageway connecting the hollow rotatable carrier drive shaft to the enclosed pressure chamber.

3. The apparatus of claim 2 where the controlled-pressure air or controlled-pressure fluid in the sealed enclosed pressure chamber acts on the rotatable workpiece carrier plate top surface where the controlled-pressure air or controlled-pressure fluid pressure is transmitted through the rotatable workpiece carrier plate thickness, wherein this controlled-pressure air or controlled-pressure fluid pressure is transmitted to the at least one workpiece that is attached to the rotatable workpiece carrier plate, wherein the controlled-pressure air or controlled-pressure fluid provides an abrading pressure which acts uniformly on the at least one workpiece and forces the at least one flat workpiece bottom surface into flat-surfaced abrading contact with the rotatable abrading platen abrading surface when the rotatable bellows spring device is flexed in a vertical direction by changing the pressure of the controlled-pressure air or controlled-pressure fluid in the sealed enclosed pressure chamber.

4. The apparatus of claim 2 where controlled vacuum is applied to the sealed enclosed pressure chamber wherein the controlled vacuum negative pressure acts on the rotatable workpiece carrier plate top surface and compresses the rotatable bellows spring device which is flexed in a vertical direction by applying the controlled vacuum negative pressure in the sealed enclosed pressure chamber and the rotatable workpiece carrier plate is raised away from the rotatable abrading platen abrading surface.

5. The apparatus of claim 1 where a flexible fluid or vacuum passageway tube is attached to the hollow rotatable carrier drive shaft and is routed to fluid passageways that are connected to fluid port holes in the rotatable workpiece carrier plate flat bottom surface where i) vacuum can be applied through the flexible fluid or vacuum passageway tube to attach the flat-surfaced at least one workpiece to the rotatable workpiece carrier plate flat bottom surface or ii) controlled-pressure air or controlled-pressure fluid can be applied through the flexible fluid or vacuum passageway tube to separate the attached flat-surfaced at least one workpiece from the rotatable workpiece carrier plate flat bottom surface.

6. The apparatus of claim 1 where a flexible annular debris band that is impervious to water, abrading fluids and abrading debris comprises a flexible elastomer or flexible polymer material where the flexible annular debris band is attached to the rotatable drive plate and to the rotatable workpiece carrier plate, wherein the flexible annular debris band surrounds the outer diameter of the rotatable bellows spring device individual annular ring outer diameters to prevent contamination of the rotatable bellows spring device individual annular rings by water, abrading fluids and abrading debris.

7. The apparatus of claim 3 where the rotatable workpiece carrier plate is flexible in a vertical direction but is substantially rigid in a horizontal direction wherein portions of the rotatable workpiece carrier plate flat bottom surface can be distorted out-of-plane by the controlled-pressure air or controlled-pressure fluid in the sealed enclosed pressure chamber which acts on the rotatable workpiece carrier plate top surface, wherein the controlled-pressure air or controlled-pressure fluid pressure is applied to the flexible rotatable workpiece carrier plate and the flexible rotatable workpiece carrier plate flat bottom surface can assume a non-flat shape.

8. The apparatus of claim 7 where multiple rotatable bellows spring devices are positioned concentric with respect to each other to form independent annular or circular rotatable bellows spring devices'"'"' sealed enclosed pressure chambers and where sealed enclosed pressure chambers are formed between adjacent sealed enclosed pressure chambers, wherein each independent sealed rotatable bellows spring device sealed enclosed pressure chamber has an independent controlled-pressure air or controlled-pressure fluid source to provide independent controlled-pressure air or controlled-pressure fluid pressures to the respective rotatable bellows spring device'"'"'s sealed enclosed pressure chambers, wherein the flexible rotatable workpiece carrier plate bottom surface assumes a non-flat shapes at the location of each independent rotatable bellows spring device'"'"'s sealed enclosed pressure chamber and the respective rotatable bellows spring device'"'"'s sealed enclosed pressure chambers apply independently controlled abrading pressures to the portions of the at least one workpiece abraded surface that is positioned on the flexible rotatable workpiece carrier plate at the respective rotatable bellows spring device'"'"'s sealed enclosed pressure chambers.

9. The apparatus of claim 1 where the rotatable workpiece carrier plate outer diameter outer periphery surface has a spherical shape.

10. The apparatus of claim 1 where the rotatable workpiece carrier plate outer diameter outer periphery surface has a spherical shape such that the spherical center of the rotatable workpiece carrier plate outer diameter outer periphery surface spherical shape is located at or near to the abraded surface of the at least one workpiece and rotatable roller idler outer shells periphery surface areas are spherical-shaped surfaces, wherein the centers of the rotatable roller idler spherical shape'"'"'s spheres are respectively located at or near to the abraded surface of the at least one workpiece such that the rotatable workpiece carrier plate rotates with spherical-action about the spherical center of the rotatable workpiece carrier plate outer diameter outer periphery surface spherical shape sphere.

11. A process of providing abrading workpieces using an abrading machine workpiece substrate carrier apparatus comprising:

a) providing a movable nominally-horizontal stationary-positioned carrier housing having an outer periphery and an outer periphery area that is nominally-horizontal and is adjacent to the stationary-positioned carrier housing outer periphery and having rotary bearings that support a vertical hollow rotatable carrier drive shaft having a carrier drive shaft cross-section and a carrier drive shaft length and a carrier drive shaft axis of rotation that is concentric to the carrier drive shaft cross-section and extends along the length of the carrier drive shaft, wherein the carrier drive shaft is fixed vertically to the stationary-positioned carrier housing where the stationary-positioned carrier housing can be moved in a vertical direction;

b) providing a circular rotatable drive plate having a rotatable drive plate outer diameter, a rotatable drive plate top surface and an opposed rotatable drive plate bottom surface, wherein both the rotatable drive plate top surface and the rotatable drive plate bottom surface are nominally horizontal and the rotatable drive plate has a rotation axis that is perpendicular to the rotatable drive plate top surface and is located at the center of the rotatable drive plate top surface, wherein the rotatable drive plate top surface is attached to and is supported by the carrier drive shaft, and wherein the carrier drive shaft axis of rotation is concentric with the rotatable drive plate rotation axis;

c) providing a rotatable bellows spring device having multiple annular rings of flat-surfaced metal or polymers having annular ring outer diameters and annular ring inside diameters where adjacent annular rings are joined together at their outer diameters and adjacent annular rings are joined together at their inner diameters to form the rotatable bellows spring device, wherein the multiple individual annular rings are nominally horizontal and the individual annular rings are flexible in a vertical direction and where the rotatable bellows spring device has a rotatable bellows spring device top annular ring and a rotatable bellows spring device bottom annular ring and where the rotatable bellows spring device has a nominally-vertical axis of rotation that is perpendicular to the rotatable bellows spring device nominally-horizontal top annular ring and the rotatable bellows spring device axis of rotation is located at the center of the rotatable bellows spring device top annular ring wherein the rotatable bellows spring device can flex in a vertical direction;

d) providing the rotatable bellows spring device individual annular ring outer diameters as approximately the same and providing the rotatable bellows spring device individual annular ring outer diameters as approximately the same as the rotatable drive plate outer diameter, wherein the rotatable bellows spring device top annular ring is attached to the rotatable drive plate bottom surface such that the rotatable bellows spring device axis of rotation is nominally-coincident with the rotatable drive plate rotation axis;

e) providing a circular rotatable workpiece carrier plate having a rotatable workpiece carrier plate top surface and an opposed rotatable workpiece carrier plate flat bottom surface wherein both the rotatable workpiece carrier plate top surface and the rotatable workpiece carrier plate bottom surface are nominally horizontal and the rotatable workpiece carrier plate has a rotation axis that is perpendicular to the rotatable workpiece carrier plate top surface and is located at the center of the rotatable workpiece carrier plate top surface, wherein the rotatable workpiece carrier plate has a rotatable workpiece carrier plate outer diameter that is approximately the same as the rotatable bellows spring device individual annular ring outer diameters and wherein the rotatable workpiece carrier plate has a rotatable workpiece carrier plate thickness and a rotatable workpiece carrier plate outer periphery surface that is located at the rotatable workpiece carrier plate outer diameter and extends from the rotatable workpiece carrier plate top surface to the rotatable workpiece carrier plate flat bottom surface;

f) attaching the rotatable bellows spring device bottom annular ring to the rotatable workpiece carrier plate top surface so that the rotatable bellows spring device axis of rotation is nominally-coincident with the rotatable workpiece carrier plate rotation axis;

g) providing at least two roller idlers having respective stationary nominally-vertical roller idler shafts having respective stationary roller idler shaft lengths, wherein the respective at least two stationary roller idler shafts are attached to the stationary-positioned carrier housing outer periphery in the stationary-positioned carrier housing outer periphery area where the respective at least two stationary roller idler shafts support respective roller idler bearings that support respective rotatable roller idler shells where the respective rotatable roller idler outer shells have a roller idler outer shell periphery and a roller idler outer shell periphery surface area that is nominally-vertical, rotating the respective rotatable roller idler outer shells about a rotation axis that is concentric with the roller idler shafts and extend along the respective roller idler shafts lengths, wherein the respective rotation axes of the respective roller idler shafts are nominally-vertical;

h) attaching the at least two multiple roller idlers to the stationary-positioned carrier housing outer periphery area around the stationary-positioned carrier housing outer periphery wherein the at least two respective rotatable roller idler outer shells periphery surface areas are positioned in contact with the rotatable workpiece carrier plate outer diameter rotatable workpiece carrier plate outer periphery surface wherein the at least two multiple roller idlers are in rolling contact with the rotatable workpiece carrier plate outer periphery surface as the rotatable workpiece carrier plate is rotated and the at least two multiple roller idlers maintain the rotatable workpiece carrier plate rotation axis to be concentric with the carrier drive shaft axis of rotation as the rotatable workpiece carrier plate is being rotated;

i) providing at least one workpiece having parallel opposed flat workpiece top surfaces and flat workpiece bottom surfaces that are attached to the rotatable workpiece carrier plate flat bottom surface, wherein the at least one workpiece top surface is attached to the rotatable workpiece carrier plate flat bottom surface;

j) providing a rotatable abrading platen having a flat abrasive coated abrading surface that is nominally horizontal;

k) moving the stationary-positioned carrier housing vertically to position the flat workpiece bottom surface into flat-surfaced abrading contact with the rotatable abrading platen abrading surface and moving that the stationary-positioned carrier housing vertically to move the flat workpiece bottom surface from flat-surfaced abrading contact with the rotatable abrading platen abrading surface; and

l) abrading the at least one workpiece.

12. The process of claim 11 where the rotatable bellows spring device top annular ring is attached to the rotatable drive plate bottom surface and the spring device bottom annular ring is attached to the rotatable workpiece carrier plate top surface, and creating a sealed enclosed pressure chamber formed in an internal volume that is contained by the rotatable bellows spring device, the rotatable drive plate bottom surface and the rotatable workpiece carrier plate top surface, and sealing the rotatable bellows spring device, the rotatable drive plate bottom surface and the rotatable workpiece carrier plate top surface by pressure and vacuum seals, wherein the rotatable drive attached to the rotatable drive plate bottom surface and the rotatable bellows plate bottom surface are pressure and vacuum sealed, and wherein the rotatable workpiece carrier plate top surface is pressure and vacuum sealed by introducing controlled-pressure air or controlled-pressure fluid or vacuum into the sealed enclosed pressure chamber through a fluid passageway that connects the hollow rotatable carrier drive shaft to the enclosed pressure chamber.

13. The process of claim 12 where the controlled-pressure air or controlled-pressure fluid in the sealed enclosed pressure chamber acts on the rotatable workpiece carrier plate top surface such that the controlled-pressure air or controlled-pressure fluid pressure is transmitted through the rotatable workpiece carrier plate thickness, wherein this controlled-pressure air or controlled-pressure fluid pressure is transmitted to the at least one workpiece that is attached to the rotatable workpiece carrier plate, wherein the controlled-pressure air or controlled-pressure fluid provides an abrading pressure which acts uniformly on the at least one workpiece being abraded and forces the at least one flat workpiece bottom surface into flat-surfaced abrading contact with the rotatable abrading platen abrading surface as the rotatable bellows spring device is flexed in a vertical direction by changing the pressure of the controlled-pressure air or controlled-pressure fluid in the sealed enclosed pressure chamber.

14. The process of claim 12 where controlled vacuum is applied to the sealed enclosed pressure chamber where the controlled vacuum negative pressure acts on the rotatable workpiece carrier plate top surface and compresses the rotatable bellows spring device which is flexed in a vertical direction by applying the controlled vacuum negative pressure in the sealed enclosed pressure chamber wherein the rotatable workpiece carrier plate is raised away from the rotatable abrading platen abrading surface.

15. The process of claim 11 where a flexible fluid or vacuum passageway tube is attached to the hollow rotatable carrier drive shaft and is routed to fluid passageways that are connected to fluid port holes in the rotatable workpiece carrier plate flat bottom surface, and vacuum is applied through the flexible fluid or vacuum passageway tube to attach flat-surfaced the at least one workpiece to the rotatable workpiece carrier plate flat bottom surface or controlled-pressure air or controlled-pressure fluid is applied through the flexible fluid or vacuum passageway tube to separate the attached flat-surfaced at least one workpiece from the rotatable workpiece carrier plate flat bottom surface.

16. The process of claim 11 where a flexible annular debris band that is impervious to water, abrading fluids and abrading debris comprises a flexible elastomer or polymer material and wherein the flexible annular debris band is attached to the rotatable drive plate and is attached to the rotatable workpiece carrier plate and the flexible annular debris band surrounds the outer diameter of the rotatable bellows spring device individual annular ring outer diameters, the flexible annular debris band blocking contamination of the rotatable bellows spring device individual annular rings by water, abrading fluids and abrading debris.

17. The process of claim 13 where a rotatable workpiece carrier plate is provided that is flexible in a vertical direction but is substantially rigid in a horizontal direction wherein portions of the rotatable workpiece carrier plate flat bottom surface can be distorted out-of-plane by the controlled-pressure air or controlled-pressure fluid that exists in the sealed enclosed pressure chamber which acts on the rotatable workpiece carrier plate top surface, wherein the controlled-pressure air or controlled-pressure fluid pressure is applied to the flexible rotatable workpiece carrier plate to cause the flexible rotatable workpiece carrier plate flat bottom surface to assume a non-flat shape.

18. The process of claim 17 where multiple rotatable bellows spring devices are provided that are positioned to be concentric with each other to form independent annular or circular rotatable bellows spring device'"'"'s sealed enclosed pressure chambers sealed enclosed pressure chambers and sealed enclosed pressure chambers are formed between adjacent sealed enclosed pressure chambers, wherein each independent sealed rotatable bellows spring device sealed enclosed pressure chamber has an independent controlled-pressure air or controlled-pressure fluid source to provide independent controlled-pressure air or controlled-pressure fluid pressures to the respective rotatable bellows spring device'"'"'s sealed enclosed pressure chambers, and the flexible rotatable workpiece carrier plate bottom surface assumes a non-flat shape at the location of each independent rotatable bellows spring device'"'"'s sealed enclosed pressure chamber, wherein the respective rotatable bellows spring device'"'"'s sealed enclosed pressure chambers apply independently controlled abrading pressures to the portions of the at least one workpiece abraded surface that is positioned on the flexible rotatable workpiece carrier plate at the location of the respective rotatable bellows spring device'"'"'s sealed enclosed pressure chambers.

19. The process of claim 11 where the rotatable workpiece carrier plate outer diameter outer periphery surface has a spherical shape and the spherical center of the rotatable workpiece carrier plate outer diameter outer periphery surface spherical shape is located at or near to the abraded surface of the at least one workpiece and the rotatable roller idler outer shells periphery surface areas are spherical-shaped surfaces, wherein the centers of the rotatable roller idler spherical shape'"'"'s spheres are respectively located at or near to the abraded surface of the at least one workpiece wherein the rotatable workpiece carrier plate are rotated with spherical-action about the spherical center of the rotatable workpiece carrier plate outer diameter outer periphery surface spherical shape sphere.