Low-temperature methods for spontaneous material spalling

Abstract

Method to (i) introduce additional control into a material spalling process, thus improving both the crack initiation and propagation, and (ii) increase the range of selectable spalling depths are provided. In one embodiment, the method includes providing a stressor layer on a surface of a base substrate at a first temperature which is room temperature. Next, the base substrate including the stressor layer is brought to a second temperature which is less than room temperature. The base substrate is spalled at the second temperature to form a spalled material layer. Thereafter, the spalled material layer is returned to room temperature, i.e., the first temperature.

1 . A method for removing a material layer from a surface of a base substrate, said method comprising:
 providing a stressor layer on a surface of a base substrate at a first temperature which is room temperature;   bringing the base substrate including the stressor layer to a second temperature which is less than room temperature;   spalling the base substrate at the second temperature to form a spalled material layer; and   returning the spalled material layer to room temperature.   
     
     
         2 . The method of  claim 1 , wherein said base substrate has a fracture toughness that is lower than that of the stressor layer. 
     
     
         3 . The method of  claim 2 , wherein said base substrate comprises a semiconductor material, a glass, or a ceramic. 
     
     
         4 . The method of  claim 3 , wherein said base substrate is a semiconductor substrate, and said semiconductor substrate is single crystalline. 
     
     
         5 . The method of  claim 1 , further comprising forming a metal-containing adhesive layer between said stressor layer and said base substrate. 
     
     
         6 . The method of  claim 1 , wherein said stressor layer is a metal, a polymer, a spall inducing tape layer or any combination thereof. 
     
     
         7 . The method of  claim 1 , wherein said stressor layer is a metal, and said metal comprises Ni, Cr, Fe or W. 
     
     
         8 . The method of  claim 1 , wherein said stressor layer is a spall inducing tape layer, and said spall inducing tape layer is a pressure sensitive tape that is flexible and stress free at said first temperature, yet ductile and tensile at the second temperature. 
     
     
         9 . The method of  claim 8 , wherein said pressure sensitive tape comprises at least an adhesive layer and a base layer. 
     
     
         10 . The method of  claim 1 , wherein the stressor layer comprises a two-part stressor layer including a lower part and an upper part, said upper part comprising a spall inducing tape layer. 
     
     
         11 . The method of  claim 1 , further comprising forming a handle substrate atop said stressor layer and at said first temperature. 
     
     
         12 . The method of  claim 1 , wherein said second temperature is 77 K or less. 
     
     
         13 . A method for removing a material layer from a surface of a base substrate, said method comprising:
 providing a stressor layer on a surface of a base substrate at a first temperature which is room temperature;   bringing the base substrate including the stressor layer to a second temperature of less than 206 K;   spalling the base substrate at the second temperature to form a spalled material layer; and   returning the spalled material layer to room temperature.   
     
     
         14 . The method of  claim 13 , further comprising forming a metal-containing adhesive layer between said stressor layer and said base substrate. 
     
     
         15 . The method of  claim 13 , wherein said stressor layer is a metal, and said metal comprises Ni, Cr, Fe or W. 
     
     
         16 . The method of  claim 13 , wherein said stressor layer is a spall inducing tape layer, and said spall inducing tape layer is a pressure sensitive tape that is flexible and stress free at said first temperature, yet ductile and tensile at the second temperature. 
     
     
         17 . The method of  claim 13 , further comprising forming a handle substrate atop said stressor layer and at said first temperature. 
     
     
         18 . The method of  claim 13 , wherein the stressor layer comprises a two-part stressor layer including a lower part and an upper part, said upper part comprising a spall inducing tape layer. 
     
     
         19 . A method for removing a material layer from a surface of a base substrate, said method comprising:
 providing a spall inducing tape layer on a surface of a base substrate at a first temperature which is from 15° C. to 60° C.;   bringing the base substrate including the spall inducing tape layer to a second temperature which is less than room temperature;   spalling the base substrate at the second temperature to form a spalled material layer; and   returning the spalled material layer to room temperature.   
     
     
         20 . The method of  claim 19 , wherein said spall inducing tape layer is a pressure sensitive tape that is flexible and stress free at said first temperature, yet ductile and tensile at the second temperature. 
     
     
         21 . The method of  claim 20 , wherein said pressure sensitive tape comprises at least an adhesive layer and a base layer. 
     
     
         22 . The method of  claim 19 , further comprising forming a handle substrate atop said spall inducing tape layer and at said first temperature. 
     
     
         23 . The method of  claim 19 , wherein spall inducing tape layer comprises an upper part of a two-part stressor layer. 
     
     
         24 . The method of  claim 19 , wherein said second temperature is 77 K or less. 
     
     
         25 . The method of  claim 19 , wherein said second temperature is less than 206 K.