Appeal No. 1998-2342 Page 4
Application No. 08/505,739
manufacturing processes, uniformity in the area of +/- 2 to 5 percent has been demanded (page 2, lines
11-13). Therefore, we conclude that the claim at least encompasses processes in which uniformity is
maintained to within +/- 5 percent. Such an interpretation is reasonable in light of the teachings of the
specification. Furthermore, we note that claim 1 is not limited to semiconductor manufacture. Thus,
non-uniformity in excess of +/- 5 percent may also be encompassed.
In order to maintain thickness uniformity across the surfaces, the claim requires a step of
“progressively reducing target-to-substrate spacing as a function of target erosion that will vary the
distance from the substrate to the eroded sputtering surface.” This limitation requires that the target and
substrate move toward each other as the target erodes. The reduction in spacing must be progressive.
We take this to mean that the erosion must be compensated for continuously or in a stepwise fashion
throughout sputtering. The reduction in spacing is dependent on “target erosion”, however, the claim is
not limited to changing the spacing on the basis of target geometry. The phrase “target erosion” is
broad enough to encompass target erosion depth or another change in the target due to erosion. As the
sputtering surface erodes, the spacing must vary. The claim does not limit the type of variation.
Claim 14 is directed to an apparatus. The apparatus includes a substrate holder and cathode
assembly which are moveable relative to one another and a motor connected to
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