Method and apparatus for producing a nanometer thick film of black phosphorus

Abstract

A low pressure process for producing thin film crystalline black phosphorus on a substrate and a black phosphorus thin film made by the process. The process includes flowing a phosphorus-containing gas into a deposition chamber and depositing phosphorus from the phosphorus-containing gas onto the substrate in the chamber. The substrate is selected from (i) a gold substrate, a gold-tin alloy substrate, a silver substrate and a copper substrate and (ii) a substrate comprising a thin film of metal selected from gold, tin, silver, copper and alloys of the foregoing metals. The substrate and phosphorus are heated to a temperature ranging from about 350° to less than about 500° C. to form a phosphorus intermediate composition. The substrate and intermediate composition are heated to a temperature of greater than 500° C. to less than about 1000° C. convert the metal phosphorus intermediate composition to the black phosphorus thin film.

1 - 8 . (canceled) 
     
     
         9 . A low pressure process for producing thin film crystalline black phosphorus on a substrate comprising:
 depositing a metal phosphide on a substrate in a deposition chamber, wherein the metal phosphide is deposited using a process selected from the group consisting of evaporation, chemical vapor deposition and sputtering and wherein the metal is selected from the group consisting of gold, tin, silver, copper and alloys of the foregoing metals,   heating the metal phosphide to a temperature of from above 500° C. to less than about 1000° C. to form thin film black phosphorus on the metal.   
     
     
         10 - 11 . (canceled) 
     
     
         12 . The process of  claim 9 , wherein the metal phosphide is selected from the group consisting of Au 2 P 3 , Au 3 SnP 7 , Au 7 IP 10 , AgP 2 , CuP 2 . 
     
     
         13 - 16 . (canceled) 
     
     
         17 . An orthorhombic black phosphorus thin film made by a low pressure process of comprising the steps of:
 flowing a phosphorus-containing gas into a deposition chamber,   depositing phosphorus from the phosphorus-containing gas onto a substrate in the deposition chamber and heating the substrate and phosphorus to a temperature ranging from about 350° to less than about 500° C. to form a phosphorus intermediate composition, wherein the substrate is selected from the group consisting of (i) a gold substrate, a gold-tin alloy substrate, a silver substrate and a copper substrate and (ii) a substrate comprising a thin film of metal selected from the group consisting of gold, tin, silver, copper and alloys of the foregoing metals,   heating the substrate and phosphorus intermediate composition to a temperature of greater than 500° C. to Original orthorhombic black phosphorus thin film having a thickness ranging from about 1 to about 500 nanometers on the substrate.   
     
     
         18 . The orthorhombic black phosphorus thin film of  claim 17 , wherein the phosphorus-containing gas is derived from the group consisting of red phosphorus, violet phosphorus, phosphine, alkyl-phosphine. 
     
     
         19 . The orthorhombic black phosphorus thin film of  claim 17 , wherein the phosphorus intermediate composition is selected from the group consisting of gold phosphide and gold-tin phosphide. 
     
     
         20 . The orthorhombic black phosphorus thin film of  claim 17 , wherein the substrate of (ii) comprises a semiconductor wafer containing the thin film of metal.