Electro-method and apparatus for improved chemical mechanical planarization pad with uniform polish performance
AssigneeSemiquest Inc.
InventorRajeev Bajaj
Life of this patent
Estimating the term…
Abstract
A polishing pad includes a guide plate having a plurality of holes therein and being affixed to a compressible under-layer; and a plurality of conducting polishing elements each affixed to the compressible under-layer and passing through a sealed contact with a proton exchange membrane and corresponding hole in the guide plate so as to be maintained in a substantially vertical orientation with respect to the compressible under-layer but being translatable in a vertical direction with respect to the guide plate. The polishing pad may also include a slurry distribution material fastened to the guide plate by an adhesive. Pad wear sensors may also be provided in the polishing pad.
Claims19
A polishing pad, comprising:
- a guide plate having a plurality of holes therein and being affixed to a compressible under-layer;
- and
- a plurality of conducting polishing elements each affixed to the compressible under-layer and passing through (i) a proton exchange membrane with a sealed contact and (ii) a corresponding hole in the guide plate so as to be maintained in a substantially vertical orientation with respect to the compressible under-layer but being translatable in a vertical direction with respect to the guide plate.
A method, comprising,
- bringing a surface of a semiconductor wafer into contact with polishing elements of a polishing pad, said polishing elements being affixed to a compressible under-layer of said pad and being maintained in a substantially vertical orientation with respect to the compressible under-layer by a guide plate adjacent to the compressible under-layer and having a number of holes therein, each of the polishing elements passing through a respective one of the holes and also through a proton exchange membrane adjacent to the guide plate, which membrane forms a seal around said polishing elements, the polishing elements thereby being translatable in a vertical direction with respect to the guide plate;
- and
- supplying anodic solution near the surface of the wafer while flowing cathodic solution below the proton exchange membrane so as to form an electrochemical cell.
A method, comprising placing a semiconductor wafer with a copper film thereon in contact with a surface of a polishing pad and supplying a sulfuric acid/copper sulfate solution while flowing silver nitrate solution under a proton exchange membrane of the pad so as to form an electrochemical cell.
Dependencies are inferred from the claim text.