Method of making semiconductor devices through overlapping diffusions

Claim 1

The method of making semiconductor devices comprising the steps of: providing a silicon semiconductor body of a first conductivity type having at least an upper surface and a lower surface and having its atomic structure crystallographically oriented to exhibit its (100) surface nOrmal to said upper surface; anisotropically etching selected portions of said body and thereby forming a groove extending vertically into said body and terminating at a first end and extending transversely across said upper surface forming a plurality of closed members for enclosing a plurality of islands formed in said body and arranging said islands in rows and columns; coating said upper surface and said groove with an insulating layer; filling said coated groove and forming a second layer of polycrystalline silicon on said insulating layer; removing in a substantially uniform manner equal thicknesses of said body for exposing said polycrystalline silicon formed in each groove and for forming a plurality of islands of said first conductivity type and each having a planar surface and each island being separated from each other island by a plurality of insulating layers and a polycrystalline layer; forming a first diffusion mask having a first opening exposing portions of adjacent columns of islands; and diffusing a dopant material through said opening for alternating said first conductivity type material to opposite conductivity type material and simultaneously forming in a plurality of said islands an equal plurality of separate PN junctions respectively.

Claim 2

The method of making semiconductor devices comprising the steps of: providing a silicon semiconductor body of a first conductivity type having at least an upper surface and a lower surface and having its atomic structure crystallographically oriented to exhibit its (100) surface nOrmal to said upper surface; anisotropically etching selected portions of said body and thereby forming a groove extending vertically into said body and terminating at a first end and extending transversely across said upper surface forming a plurality of closed members for enclosing a plurality of islands formed in said body and arranging said islands in rows and columns; coating said upper surface and said groove with an insulating layer; filling said coated groove and forming a second layer of polycrystalline silicon on said insulating layer; removing in a substantially uniform manner equal thicknesses of said body for exposing said polycrystalline silicon formed in each groove and for forming a plurality of islands of said first conductivity type and each having a planar surface and each island being separated from each other island by a plurality of insulating layers and a polycrystalline layer; forming a first diffusion mask having a first opening exposing portions of adjacent columns of islands; and diffusing a dopant material through said opening for alternating said first conductivity type material to opposite conductivity type material and simultaneously forming in a plurality of said islands an equal plurality of separate PN junctions respectively.