Method of making porous nitrogenized titanium coatings for medical devices

Abstract

The disclosure describes a method of making porous nitrogenized titanium coated substrates. The process includes depositing titanium on a substrate using a glancing angle deposition (GLAD) process and then nitrogenizing the deposited titanium using a thermal or plasma-assisted thermal gaseous nitrogenizing process.

What is claimed is: 
     
         1 . A method comprising:
 providing a substrate having a surface;
 depositing a porous titanium film on the surface of the substrate using glancing angle deposition; and 
 converting at least a portion of the porous titanium film to a porous film comprising nitrogenized surface layers using a thermal or plasma-assisted thermal gaseous nitrogenizing process. 
   
     
     
         2 . The method according to  claim 1 , wherein the substrate is an electrode. 
     
     
         3 . The method according to  claim 1 , wherein the substrate comprises platinum or titanium or alloys of either. 
     
     
         4 . The method according to  claim 1 , wherein the porous titanium film is deposited on the surface of the substrate at a thickness of at least 1 micrometer. 
     
     
         5 . The method according to  claim 1  wherein the substrate is a metal. 
     
     
         6 . The method according to  claim 1  wherein the surface area, as determined by electrochemical impedance measurements is increased by a factor of 100 or more relative to the geometric surface area of the substrate. 
     
     
         7 . The method according to  claim 1  wherein the surface area, as determined by electrochemical impedance measurements is increased by a factor of 10 or more relative to the geometric surface area of the substrate.