Method of producing schottky contacts

Claim 1

A method as defined in claim 1 wherein the insulating material is aluminum oxide.

Claim 16

A method of producing metal-semiconductor contacts with precisely defined relatively small surface areas that include chromium on a semiconductor member, comprising the sequential steps of; (1) applying a layer of an insulating material selected from the group of aluminum oxide and silicon dioxide onto a semiconductor surface in a thickness of about 100 to 500 nm; (2) applying a layer of a photo-sensitive resist material onto the insulating material layer, selectively exposing areas of said resist material layer to light so that unexposed areas thereof correspond to desired contact areas, and removing the unexposed areas to expose corresponding insulating material areas; (3) etching the exposed insulating material areas with an etch-solution for said insulating material until corresponding areas of the semiconductor surface are exposed, and removing the exposed areas of the resist material layer to uncover corresponding insulating material areas; (4) evaporating a layer of chromium onto the exposed semiconductor surfaces and onto uncovered insulating material layer areas in a thickness of about 20 to 100 nm; and (5) removing the remained areas of insulating material with an etch-solution for said insulating material until corresponding areas of semiconductor surface are exposed and discrete areas of chromium remain on said semiconductor surface.

Claim 18

A method of producing metal-semiconductor contacts with precisely defined relatively small surface areas that include chromium on a semiconductor substrate; comprise the sequential steps of; (1) applying a layer of silicon dioxide onto a semiconductor surface in a thickness of about 100 to 500 nm; (2) applying a layer of a photo-sensitive resist material onto the silicon dioxide layer, selectively exposing areas of said resist material layer to light so that unexposed areas thereof correspond to desired contact areas and removing the unexposed areas to expose corresponding silicon dioxide areas; (3) etching the exposed silicon dioxide layer areas with an etch-solution comprised of a mixture of hydrofluoric acid, ammonium fluoride and water until corresponding areas of the semiconductor surface are exposed and removing the exposed areas of the resist material layer to uncover corresponding silicon dioxide layer areas; (4) evaporatIng a layer of chromium onto the exposed semiconductor surface areas and onto uncovered silicon dioxide layer areas in a thickness of about 20 to 100 nm; (5) removing the areas of insulating material with said etch-solution until corresponding areas of semiconductor surface are exposed and discrete areas of chromium remain on said semiconductor surface; (6) applying a coating of silicon dioxide over the exposed semiconductor surface areas and the discrete chromium areas; (7) applying a layer of a photo-sensitive resist material onto said silicon dioxide layer, selectively exposing areas of said resist material layer to light so that unexposed areas thereof generally correspond to the discrete chromium areas, and removing said unexposed areas to expose corresponding areas of the silicon dioxide layer; (8) etching the exposed silicon dioxide layer areas with said etch-solution to expose at least portions of the discrete chromium areas; and (9) evaporating a layer of aluminum onto at least said exposed chromium area portions in a thickness of about 50 to 100 nm.