Appeal 2007-4189
Application 10/164,986
strengths and good thermal insulation properties in the composite shadow
rings of the AAPA (Answer 4).
Appellants contend that there is no motivation to combine Tolles,
Flach, and Clark with the AAPA because there is no correlation between the
semiconductor fabrication equipment art and the construction industry art
(Br. 7-8). Accordingly, we determine that the issue presented is as follows:
Has the Examiner made sufficient factual findings such that it is reasonable
to conclude that one of ordinary skill in the art would have been led to
combine the teachings of the references in the manner claimed within the
meaning of 35 U.S.C. § 103? We answer this question in the negative. The
issue turns on whether the Flach and Clark references are analogous to the
semiconductor fabrication equipment art.
The Specification describes the AAPA as following:
In still another improved design of composite shadow ring,
shown in Figures 2 and 2A, the composite shadow ring 50,
shown in a cross-sectional view in Figure 2 and in a plane view
in Figure 2A, is constructed by an upper ring 54 and a lower ring
56. The advantage of this configuration of two flat, concentric
rings assembled together by locating pins 60 is that only the
upper ring 54 is exposed to the plasma ions in the etch chamber
and therefore, only the upper ring 54 is subjected to the etching
effect of the plasma. As a result, only the upper ring 54 needs to
be replaced after repeated usage of the composite shadow ring
50. For instance, a commercially available composite shadow
ring 50 is constructed by an upper ring 54 fabricated of silicon
and a lower ring 56 fabricated of silicon dioxide.
While the composite shadow ring 50 shown in Figure 2
presents the benefit that only the upper ring 54 is subjected to
plasma corrosion and therefore only the upper ring 54 needs to
be replaced, it presents a processing problem in that the lower
ring 56 is difficult to clean during a preventive maintenance
procedure. The locating pins 60 which are formed of quartz
4
Page: Previous 1 2 3 4 5 6 7 8 Next
Last modified: September 9, 2013