Low resistance indium oxide coatings

Claim 1

In a method for depositing a transparent electroconductive coating consisting essentially of the oxide of at least one metal having an atomic number between 48 and 51 comprising the steps of supporting a substate in an atmosphere comprising an inert gas and sufficient oxygen to effect oxide formation at a pressure of less than about 10 -1 Torr, heating the substrate, and cathode sputtering a metallic target to deposit said oxide onto said substrate until a coating of desired thickness is formed, the improvement which comprises carrying out the cathode sputtering in at least two steps at substantially different temperatures whereby a. a thin layer of oxide constituting the minor portion of the final oxide layer is deposited at a temperature of T 1 ; b. the deposition is interrupted while the substrate is heated; and c. subsequently, the major portion of the final oxide layer is deposited at a temperature T 2 wherein T 1 which is less than about 200° F. (about 94° C.) is substantially lower than T 2 which is at least about 400° F. (about 204° C.).