US 2006/0067160 A1 · Apparatus for forming a polishing pad having a reduced striations

Abstract

The present invention provides an apparatus 20 for forming a striation-reduced chemical mechanical polishing pad 4. The polishing pad 4 comprises a first delivery line 66 for delivering a polymeric material 52 into a mixer 68 and a second delivery line 44 for delivering microspheres 48 into the mixer 68 with the polymeric material 52. The second delivery line 44 is connected to a bulk density control unit 21. The bulk density control unit 21 comprises a storage hopper 22 for storing the microspheres 48. The storage hopper 22 further comprises a porous membrane 24 provided over a plenum 26. A fluidizing gas source 23 is connected to the plenum 26 through a gas inlet line 27. Gas 28 fed into the plenum 26 from the fluidizing gas source 23 permeates through the porous membrane 24 and reduces the initial bulk density of the microspheres 48 in the storage hopper 22.

Claims10

Dependent claims

An apparatus for forming a striation-reduced chemical mechanical polishing pad, comprising:

a first delivery line for delivering a polymeric material into a mixer;
a second delivery line for delivering microspheres having an initial bulk density into the mixer with the polymeric material, the second delivery line being connected to a bulk density control unit, the bulk density control unit comprising:
a storage hopper for storing the microspheres, wherein the storage hopper further comprises a porous membrane provided over a plenum;
a fluidizing gas source connected to the plenum through a gas inlet line;
and
wherein gas fed into the plenum from the fluidizing gas source permeates through the porous membrane and reduces the initial bulk density of the microspheres in the storage hopper.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

10/956,844Filed 30 Sep 2004

Published

30 Mar 2006

Term ends

Not estimatedThe source records don’t support an estimate.

Classification13 codes

B24D 18/009
Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for: tools not otherwise provided for
B29B 7/726
Measuring, controlling or regulating: measuring properties of mixture, e.g. temperature or density
B29B 7/7457
Using other mixers or combinations of mixers, e.g. of dissimilar mixers ; Plant: mixing heads without moving stirrer
B29B 7/7471
Using other mixers or combinations of mixers, e.g. of dissimilar mixers ; Plant: mixers in which the mixing takes place at the inlet of a mould,…

Apparatus for forming a polishing pad having a reduced striations

Life of this patent

Apparatus for forming a polishing pad having a reduced striations

Life of this patent

Abstract

Claims10