Methods of making composite conductive structures in integrated circuits
First Claim
1. A method of forming a composite structure comprisingproviding a substrate of semiconductor material having an overlying layer of insulating material,forming a conductor of a refractory metal which is substantially nonreactive with silicon dioxide in a desired pattern overlying said layer of insulating material,forming over said conductor of metallic material and said layer of insulating material a layer of polycrystalline silicon,heating said substrate including said conductor of metallic material and said overlying layer of polycrystalline silicon to a temperature and for a time to cause said layer of polycrystalline silicon to react with a portion of said conductor to form a layer of a silicide of said metallic material overlying a remaining portion of said conductor unconverted to a silicide thereof,removing the portion of said layer of polycrystalline silicon which has not reacted with said metallic material,heating said substrate including said conductor and said layer of said metal silicide in an oxidizing atmosphere at a temperature and for a time to cause said oxidizing atmosphere to react with said layer of said silicide to convert a portion thereof to silicon dioxide overlying another portion of said layer of said silicide unconverted to silicon dioxide.
0 Assignments
0 Petitions
Accused Products
Abstract
A method of making a composite conductive structure is described. The structure includes an insulating substrate on which is provided a conductor of a refractory metal substantially nonreactive with silicon dioxide covered by a layer of a silicide of the refractory metal and a layer of silicon dioxide. The method includes depositing a layer of polycrystalline silicon over the conductor and the insulating substrate, reacting the layer of polycrystalline silicon with the conductor to form a refractory metal silicide, removing the unreacted portion of the layer of polycrystalline silicon, and then oxidizing the exposed surface of the refractory metal silicide into a layer of silicon dioxide.
-
Citations
16 Claims
-
1. A method of forming a composite structure comprising
providing a substrate of semiconductor material having an overlying layer of insulating material, forming a conductor of a refractory metal which is substantially nonreactive with silicon dioxide in a desired pattern overlying said layer of insulating material, forming over said conductor of metallic material and said layer of insulating material a layer of polycrystalline silicon, heating said substrate including said conductor of metallic material and said overlying layer of polycrystalline silicon to a temperature and for a time to cause said layer of polycrystalline silicon to react with a portion of said conductor to form a layer of a silicide of said metallic material overlying a remaining portion of said conductor unconverted to a silicide thereof, removing the portion of said layer of polycrystalline silicon which has not reacted with said metallic material, heating said substrate including said conductor and said layer of said metal silicide in an oxidizing atmosphere at a temperature and for a time to cause said oxidizing atmosphere to react with said layer of said silicide to convert a portion thereof to silicon dioxide overlying another portion of said layer of said silicide unconverted to silicon dioxide.
Specification