Appeal 2007-0236
Application 09/934,474
The Appellants invented an apparatus and method for polishing a
semiconductor substrate with a polishing solution which comprises an
abrasive slurry, an additive, and pure water. According to the Appellants'
disclosure, when these ingredients are mixed together prior to use, abrasive
grains coagulate thereby forming undesirable coarse grains which cause
unacceptable scratch of the semiconductor substrate (Specification 3-4).
The invention avoids this problem by separately spraying each of these
ingredients as a mist (Specification 4-5). In one embodiment, these
ingredients are sprayed as a mist into a mixing unit to form a polishing
mixture and the mixing unit supplies the polishing mixture onto the
polishing table (Fig. 8). In another embodiment, the ingredients are sprayed
as a mist onto the polishing table so they mix together on the table
(Fig. 7). These embodiments are represented by independent claims 1 and 2
respectively, which read as follows:
1. An apparatus including a polishing solution supply system, the
polishing solution supply system comprising:
a polishing table for placing a semiconductor substrate on a major
surface thereof;
a first supply unit for spraying and supplying a mist comprising
abrasive slurry;
a second supply unit for spraying and supplying a mist comprising
additive;
a third supply unit for spraying and supplying a mist comprising pure
water; and
a mixing unit for mixing the mist of abrasive slurry supplied from said
first supply unit, the mist of additive supplied from said second supply unit
2
Page: Previous 1 2 3 4 5 6 7 Next
Last modified: September 9, 2013