Appeal No. 1997-3916
Application No. 08/429,650
The examiner's position (answer page 7) is that the final structure of the Miyamoto device has
region (6) formed narrower and only under the gate electrode (3), and that regions (6) and (7) in effect
form two different regions as evidenced by the fact that the two regions (6) and (7) have different
concentration levels. Claim 25 recites "a buried layer . . . forming a buried anti-punchthrough implant
channel". We find that in Miyamoto (figure 12) high concentration region (6)
is formed in the whole channel region (col. 4, lines 62-68) and that after forming the gate electrode (3) ion
implantation is carried out using the gate electrode (3) as a mask in the forming of the high concentration
region (7). Miyamoto states (col. 5, lines 1-3) that "[a]ccording to this method, the high concentration
region 7 can be formed in self aligned from the edge of the gate electrode 3 in definite penetrating depth
irrespective of the gate length." and that high concentration region (7) enters by the definite distance Lp
from the channel edge (figure 1 and col. 6, lines 55-57).
We agree with the examiner that in the final product, the high concentration regions (6)
and (7) form different regions due to their different concentrations levels. However, we find that the high
concentration regions (6)(7) function together to suppress punchthrough (col.. 7, lines 3-6). Since high
concentration regions (6) and (7) cooperate together to suppress punchthrough, and extend beyond the
gate electrode (3), we find that the claim language of "a buried layer of implanted boron ions . . . forming a
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