Methods for forming thermoelectric elements

Abstract

The present disclosure provides a method for forming a thermoelectric device, comprising providing a semiconductor substrate and providing a first layer of an etching material adjacent to the semiconductor substrate. The etching material facilitates the etching of the semiconductor substrate upon exposure to an oxidizing agent and a chemical etchant. Next, a second layer of a semiconductor oxide is provided adjacent to the first layer, and the second layer is patterned to form a pattern of holes or wires. The second layer and first layer are then sequentially etched to expose portions of the semiconductor substrate. Exposed portions of the semiconductor substrate are then contacted with an oxidizing agent and a chemical etchant to transfer the pattern to the semiconductor substrate.

What is claimed is: 
     
         1 . A method for forming a thermoelectric element having a figure of merit (ZT) that is at least about 0.2, comprising:
 (a) providing a chamber comprising a first substrate in contact with a second substrate, wherein said first substrate and said second substrate are disposed between and in electrical communication with a plurality of electrodes; and   (b) using said plurality of electrodes to apply an electrical potential across said first substrate and said second substrate to direct electrical current through said first substrate and said second substrate while applying a pressure of greater than or equal to about 10 atm to said first substrate and said second substrate to form a thermoelectric element comprising a pattern of holes, wherein said thermoelectric element has said ZT that is at least about 0.2.   
     
     
         2 . The method of  claim 1 , wherein said pressure is greater than or equal to about 100 atm. 
     
     
         3 . The method of  claim 2 , wherein said pressure is greater than or equal to about 1000 atm. 
     
     
         4 . A method for forming a thermoelectric element having a figure of merit (ZT) that is at least about 0.2, comprising:
 (a) providing a chamber comprising a first substrate in contact with a second substrate, wherein said first substrate and said second substrate are disposed between and in electrical communication with a plurality of electrodes; and   (b) using said plurality of electrodes to apply an electrical potential across said first substrate and said second substrate to direct electrical current through said first substrate and said second substrate to form a thermoelectric element comprising a pattern of holes, wherein said thermoelectric element is formed at a temperature from about 100° C. and 1000° C., and wherein said thermoelectric element has a ZT that is at least about 0.2.   
     
     
         5 . The method of  claim 1 , wherein said first substrate or said second substrate comprises one or more members selected from the group consisting of bismuth, antimony, and tellurium. 
     
     
         6 . The method of  claim 6 , wherein each of said first substrate and said second substrate comprises one or more members selected from the group consisting of bismuth, antimony, and tellurium. 
     
     
         7 . The method of  claim 1 , wherein said ZT is at least about 0.5. 
     
     
         8 . The method of  claim 7 , wherein said ZT is at least about 1. 
     
     
         9 . The method of  claim 8 , wherein said ZT is at least about 1.5. 
     
     
         10 . The method of  claim 1 , wherein said first substrate or said second substrate does not include a metallic coating. 
     
     
         11 . The method of  claim 1 , wherein said electrical potential is applied to said first substrate and said second substrate by a direct current. 
     
     
         12 . The method of  claim 1 , wherein said electrical potential is between about 1 volt and 1000 volts. 
     
     
         13 . The method of  claim 12 , wherein said electrical potential is between about 10 volts and 500 volts. 
     
     
         14 . The method of  claim 13 , wherein said electrical potential is between about 20 volts and 200 volts. 
     
     
         15 . A method for forming a thermoelectric element having a figure of merit (ZT) that is at least about 0.2, comprising:
 (a) providing a chamber comprising a first substrate in contact with a second substrate, wherein said first substrate and said second substrate are disposed between and in electrical communication with a plurality of electrodes, wherein said chamber comprises an inert gas; and   (b) using said plurality of electrodes to apply an electrical potential across said first substrate and said second substrate to direct electrical current through said first substrate and said second substrate to form a thermoelectric element comprising a pattern of holes, wherein said thermoelectric element has a ZT that is at least about 0.2.   
     
     
         16 . The method of  claim 15 , wherein said inert gas comprises nitrogen, argon, or helium. 
     
     
         17 . The method of  claim 1 , wherein said first substrate or said second substrate has a dimension from about 10 micrometers to 500 micrometers. 
     
     
         18 . The method of  claim 4 , wherein said first substrate or said second substrate does not include a metallic coating. 
     
     
         19 . The method of  claim 4 , wherein said electrical potential is applied to said first substrate and said second substrate by a direct current. 
     
     
         20 . The method of  claim 4 , wherein said ZT is at least about 0.5. 
     
     
         21 . The method of  claim 20 , wherein said ZT is at least about 1. 
     
     
         22 . The method of  claim 21 , wherein said ZT is at least about 1.5. 
     
     
         23 . The method of  claim 15 , wherein said first substrate or said second substrate does not include a metallic coating. 
     
     
         24 . The method of  claim 15 , wherein said electrical potential is applied to said first substrate and said second substrate by a direct current. 
     
     
         25 . The method of  claim 15 , wherein said ZT is at least about 0.5. 
     
     
         26 . The method of  claim 25 , wherein said ZT is at least about 1. 
     
     
         27 . The method of  claim 26 , wherein said ZT is at least about 1.5.