Appeal No. 96-1584
Application 08/066,697
breakdown voltage characteristic of the device at PN junction 31,
the bias voltage V is set at a value which is the same as or
b
close to the voltage applied to the island 11. The bias voltage
can differ from the island voltage by a value no more than half
the total voltage applied to the integrated circuit.
THE PRIOR ART
In FIG. 2, Muramatsu discloses a sectional view of the
semiconductor device illustrated in FIG. 1. N- island region 12A
is formed on a P type semiconductor substrate 10. These elements
correspond to appellant's island region 11 and substrate 13 in
FIG. 3. N+ buried region 11A, corresponding to appellant's N+
region 25, is formed between region 12A and substrate 10.
Muramatsu's film 18a formed on the surface of isolation groove 19
corresponds to appellant's film 43 on the surface of its groove,
the polycrystalline insulation layer 20 in groove 19 corresponds
to appellant's trench fill material 45 and P type region 13
corresponds to appellant's P type region 33.
In FIG. 5g, Muramatsu discloses that the N+ buried region
33A and P-type region 31 corresponding to elements 11A and 13 of
FIG. 2, respectively, can be connected to the sidewalls of the
trench at insulation layer 18''.
6
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007