Method of manufacturing semiconductor devices

Claim 1

A method of manufacturing semiconductor devices comprising the steps of: preparing a semiconductor substrate (12) having a surface layer of silicon; forming a conductive thin film (14) of a silicide composed of a metal having a high melting point and silicon on said semiconductor substrate; forming an oxidation-resistant mask (18) on a first portion (14a) of said conductive thin film (14); and converting a second, exposed, portion (19) of said conductive thin film (14) into an insulating film (19a) of a composite oxide composed of silicon oxide and oxide of said metal by first heating said conductive thin film to a temperature in a first range sufficiently low to provide predominant oxidation of the metal having a high melting point and, thereafter, heating the structure to a temperature in a second, higher, temperature range wherein silicon in said surface layer is predominantly oxidized.

Claim 2

A method of manufacturing semiconductor devices comprising the steps of: preparing a semiconductor substrate (12) having a surface layer of silicon; forming a conductive thin film (14) of a silicide composed of a metal having a high melting point and silicon on said semiconductor substrate; forming an oxidation-resistant mask (18) on a first portion (14a) of said conductive thin film (14); and converting a second, exposed, portion (19) of said conductive thin film (14) into an insulating film (19a) of a composite oxide composed of silicon oxide and oxide of said metal by first heating said conductive thin film to a temperature in a first range sufficiently low to provide predominant oxidation of the metal having a high melting point and, thereafter, heating the structure to a temperature in a second, higher, temperature range wherein silicon in said surface layer is predominantly oxidized.

Claim 9

A method of manufacturing a semiconductor device comprising the steps of: forming a semiconductor substrate of silicon; forming a thick field oxide film in a predetermined pattern on a main surface of said semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer wherein said step of forming said composite oxide film comprises the step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask, said step of heating said semiconductor device thereby oxidizing said second portion of the conductive film not covered by said oxidation resistant mask comprising the further steps of first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide; and forming said semiconductor of silicon.

Claim 10

A method of manufacturing a semiconductor device comprising the steps of: forming a semiconductor substrate of silicon; forming a thick field oxide film in a predetermined pattern on a main surface of said semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer wherein said step of forming said composite oxide film comprises the step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask, said step of heating said semiconductor device thereby oxidizing said second portion of the conductive film not covered by said oxidation resistant mask comprising the further steps of first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide; and forming said semiconductor of silicon.

Claim 11

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer by heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask; and said step of heating said semiconductor device thereby ozidizing said second portion of the conductive film comprising the further steps of first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide.

Claim 12

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer by heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask; and said step of heating said semiconductor device thereby ozidizing said second portion of the conductive film comprising the further steps of first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide.

Claim 13

A method of manufacturing a semicondutor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprises the step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; said step of forming said composite oxide film comprising the further step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask by first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide.

Claim 14

A method of manufacturing a semicondutor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprises the step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; said step of forming said composite oxide film comprising the further step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask by first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide.

Claim 15

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprising the further step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; and said metal being selected to have a first oxidation temperature lower than an oxidation temperature for silicon.

Claim 16

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprising the further step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; and said metal being selected to have a first oxidation temperature lower than an oxidation temperature for silicon.

Claim 17

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprising the further step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; said step of forming said composite oxide film comprising the further step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask; by first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide; and said metal is selected to have a first oxidation temperature lower than an oxidation temperature for silicon.

Claim 18

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprising the further step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; said step of forming said composite oxide film comprising the further step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask; by first heating said device to a temperature greater than an oxidation temperature for said metal and thereafter heating said device to a temperature greater than an oxidation temperature for silicon thereby to convert said conductive thin film to said insulating film of composite oxide; and said metal is selected to have a first oxidation temperature lower than an oxidation temperature for silicon.

Claim 19

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprising the further step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; said step of forming said composite oxide film comprising the further step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask; and said second mentioned heating step comprising the step of first heating the device to a temperature exceeding a first oxidation temperature and thereafter increasing the temperature to a temperature exceeding a second oxidation temperature, thereby first predominantly oxidizing said metal component of said silicide and thereafter predominantly oxidizing said silicon component of said silicide to form a composite oxide film having a metal oxide layer over a semiconductor oxide layer.

Claim 20

A method of manufacturing a semiconductor device comprising the steps of: forming a thick field oxide film in a predetermined pattern on a main surface of a semiconductor substrate; forming on an exposed portion of said main surface of said substrate a thin film of a metal having a high melting point; forming on said main surface a conductive metal silicide thin film of said metal and of silicon; injecting impurities of the same conductivity type as said substrate into a first predetermined portion of said main surface of said main substrate to form an impurity layer therein; injecting impurities of an opposite conductivity type to the substrate into a second portion of the main surface of said substrate thereby forming a p-n junction therewith; forming an oxidation resistant mask on a first portion of the conductive metal silicide thin film; forming, from a second, exposed, portion of the conductive thin film not covered by said oxidation resistant mask a composite oxide film acting as an insulator and including a metal oxide layer and a semiconductor oxide layer; said step of forming on said main surface a conductive metal silicide thin film comprising the further step of heating the thin film of metal formed on said main surface, and said main surface, in a nonoxidation atmosphere to a temperature in excess of a melting point of said metal, thereby forming on an exposed surface of the substrate said conductive metal silicide thin film, while maintaining portions of said thin film on the thick field oxide in a non-reacted state, and wherein the non-reacted thin film is subsequently removed from the thick field oxide film in a selfaligning manner; said step of forming said composite oxide film comprising the further step of heating said semiconductor device thereby oxidizing said second portion of the conductive thin film not covered by said oxidation resistant mask; and said second mentioned heating step comprising the step of first heating the device to a temperature exceeding a first oxidation temperature and thereafter increasing the temperature to a temperature exceeding a second oxidation temperature, thereby first predominantly oxidizing said metal component of said silicide and thereafter predominantly oxidizing said silicon component of said silicide to form a composite oxide film having a metal oxide layer over a semiconductor oxide layer.

Claim 21

A method of manufacturing a semiconductor memory device having a plurality of cells each comprising a MOS-type field effect transistor and a capacitor, a low resistance material in a source region of said transistor forming a conductive thin film, and a dielectric material for said capacitor forming an insulating film, comprising the steps of preparing a semiconductor substrate (12) having a surface layer of silicon; forming a conductive thin film (14) of a silicide composed of a metal having a high melting point and silicon on said semiconductor substrate; forming an oxidation-resistant mask (18) on a first portion (14a) of said conductive thin film (14); and converting a second, exposed, portion (19) of said conductive thin film (14) into an insulating film (19a) of a composite oxide composed of silicon oxide and oxide of said metal by first heating said conductive thin film to a temperature in a first range sufficiently low to provide predominant oxidation of the metal having a high melting point and, thereafter, heating the structure to a temperature in a second, higher, temperature range wherein silicon in said surface layer is predominantly oxidized.

Claim 22

A method of manufacturing a semiconductor memory device having a plurality of cells each comprising a MOS-type field effect transistor and a capacitor, a low resistance material in a source region of said transistor forming a conductive thin film, and a dielectric material for said capacitor forming an insulating film, comprising the steps of preparing a semiconductor substrate (12) having a surface layer of silicon; forming a conductive thin film (14) of a silicide composed of a metal having a high melting point and silicon on said semiconductor substrate; forming an oxidation-resistant mask (18) on a first portion (14a) of said conductive thin film (14); and converting a second, exposed, portion (19) of said conductive thin film (14) into an insulating film (19a) of a composite oxide composed of silicon oxide and oxide of said metal by first heating said conductive thin film to a temperature in a first range sufficiently low to provide predominant oxidation of the metal having a high melting point and, thereafter, heating the structure to a temperature in a second, higher, temperature range wherein silicon in said surface layer is predominantly oxidized.