Method of making contact electrodes to silicon gate, and source and drain regions, of a semiconductor device

Claim 1

A method for making transistor devices in a silicon semiconductor body (10), each said device (20 or 30, FIG. 6 or FIG. 7) having a gate electrode layer contact (15) to a polycrystalline silicon gate electrode (13) during a stage of manufacture of said device, a source electrode layer contact (16), and a drain electrode layer contact (17), including the steps of coating side edges of said polysilicon gate electrode (13) with a silicon dioxide layer (14), and forming said gate and source and drain electrode contacts simultaneously by .[.depositing on.]. .Iadd.bombarding .Iaddend.said body (10) .Iadd.with .Iaddend.a transition metal capable of forming a silicide to form.Iadd., during the bombarding, .Iaddend.silicide of said metal contacting a pair of then exposed regions (10.1, 10.2) contiguous with a major surface of the body (10), thereby to form said source and drain electrode contacts (16, 17), and simultaneously to form said silicide contacting the then exposed regions of the polycrystalline silicon gate electrode (13), thereby to form said gate electrode contact (15), whereby essentially no silicide accumulates on the silicon dioxide coating (14).

Claim 2

A method for making transistor devices in a silicon semiconductor body (10), each said device (20 or 30, FIG. 6 or FIG. 7) having a gate electrode layer contact (15) to a polycrystalline silicon gate electrode (13) during a stage of manufacture of said device, a source electrode layer contact (16), and a drain electrode layer contact (17), including the steps of coating side edges of said polysilicon gate electrode (13) with a silicon dioxide layer (14), and forming said gate and source and drain electrode contacts simultaneously by .[.depositing on.]. .Iadd.bombarding .Iaddend.said body (10) .Iadd.with .Iaddend.a transition metal capable of forming a silicide to form.Iadd., during the bombarding, .Iaddend.silicide of said metal contacting a pair of then exposed regions (10.1, 10.2) contiguous with a major surface of the body (10), thereby to form said source and drain electrode contacts (16, 17), and simultaneously to form said silicide contacting the then exposed regions of the polycrystalline silicon gate electrode (13), thereby to form said gate electrode contact (15), whereby essentially no silicide accumulates on the silicon dioxide coating (14).

Claim 5

The method of claims 1 or 2 in which the step of forming is continued until the gate electrode layer (15) contacts the semiconductor body (10).

Claim 6

The method for making semiconductor apparatus comprising the steps of: (a) forming a polycrystalline silicon layer covering a first silicon dioxide layer which coats a first portion of a major surface of a silicon semiconductor body; (b) forming a second silicon dioxide layer on an exposed side edge of the polycrystalline silicon layer, leaving a major surface of a polycrystalline layer exposed and free of silicon dioxide; (c) subjecting the body to a bombardment with a metal, which forms metal-silicide, from a target of said metal under the influence of predetermined voltage applied to said body whereby layers of metal-silicide are formed.Iadd., during the bombardment, .Iaddend.at the exposed portions of the major surfaces of the semiconductor body and of the polycrystalline silicon layer and whereby essentially no .Iadd.metal or .Iaddend.metal-silicide is formed on any portion of the second silicon dioxide layer during the bombardment.

Claim 7

The method for making semiconductor apparatus comprising the steps of: (a) forming a polycrystalline silicon layer covering a first silicon dioxide layer which coats a first portion of a major surface of a silicon semiconductor body; (b) forming a second silicon dioxide layer on an exposed side edge of the polycrystalline silicon layer, leaving a major surface of a polycrystalline layer exposed and free of silicon dioxide; (c) subjecting the body to a bombardment with a metal, which forms metal-silicide, from a target of said metal under the influence of predetermined voltage applied to said body whereby layers of metal-silicide are formed.Iadd., during the bombardment, .Iaddend.at the exposed portions of the major surfaces of the semiconductor body and of the polycrystalline silicon layer and whereby essentially no .Iadd.metal or .Iaddend.metal-silicide is formed on any portion of the second silicon dioxide layer during the bombardment.

Claim 9

A method for making semiconductor apparatus comprising the steps of: (a) forming a polycrystalline silicon layer on a selected portion of a major surface of a semiconductor silicon crystal body; (b) forming a second silicon dioxide layer on an exposed side edge of the polycrystalline silicon layer, leaving a major surface of a polycrystalline layer exposed and free of oxide; (c) subjecting the body to a bombardment with a transition metal capable of forming metal-silicide under the influence of voltage applied to said body such that layers of said silicide are formed.Iadd., during the bombardment, .Iaddend.at the exposed portions of the major surfaces of the semiconductor body and of the polycrystalline silicon layer and that no .Iadd.metal or .Iaddend.metal-silicide is formed on any portion of the second silicon dioxide layer during the bombardment.

Claim 10

A method for making semiconductor apparatus comprising the steps of: (a) forming a polycrystalline silicon layer on a selected portion of a major surface of a semiconductor silicon crystal body; (b) forming a second silicon dioxide layer on an exposed side edge of the polycrystalline silicon layer, leaving a major surface of a polycrystalline layer exposed and free of oxide; (c) subjecting the body to a bombardment with a transition metal capable of forming metal-silicide under the influence of voltage applied to said body such that layers of said silicide are formed.Iadd., during the bombardment, .Iaddend.at the exposed portions of the major surfaces of the semiconductor body and of the polycrystalline silicon layer and that no .Iadd.metal or .Iaddend.metal-silicide is formed on any portion of the second silicon dioxide layer during the bombardment.

Claim 11

The method of claims 6 or 7 in which said bombardment with metal is produced by sputtering from a target of said metal upon which ions of suitable kinetic energy are incident.

Claim 12

The method of claims 6 or 7 in which an oxide isolation layer of greater thickness than the first silicon dioxide layer is embedded in a second, separate portion of the major surface of the silicon body prior to the step of subjecting the body to the bombardment, whereby no .Iadd.metal or .Iaddend.metal-silicide is formed on any portion of the oxide isolation layer.