Appeal No. 1997-3512 Page 6
Application No. 08/482,034
gap, highly doped p-type GaAlAs layer 13 on top of narrow band
gap, lighter doped p-type GaAs layer 12.” In addition, Gaw
states (page 3, col. 2, line 50 through page 4, col. 1, line
1) that “electrons which have entered base layer 13 are
influenced by an accelerating field, caused by the potential
difference between conduction band 23 and conduction band 25.
Because band 25 is at a lower potential, the accelerating
field acts to sweep electrons from layer 13 to layer 12. The
magnitude of the accelerating field is a function of doping
concentration differential and band gap differential between
layer 12 and layer 13.” As Gaw specifically provides for
different doping levels to affect the magnitude of the
accelerating field to enhance current flow, we cannot conclude
that the doping levels of the two base layers are
approximately the same. Accordingly, we will reverse the
rejection of claims 17, 18 and 20 under 35 U.S.C. § 102(b).
With regard to the alternate rejection of claims 17, 18
and 20 under 35 U.S.C. § 103, the examiner relies upon the
statement in Gaw (page 3, col. 1, lines 49-51) that “[m]ore
specifically, first base layer 12 consists of a GaAs layer,
with an acceptor concentration selected to meet desired device
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