Forming a protective layer on a mold and mold having a protective layer

Abstract

A method of forming a mold having a protective layer includes forming a mold substrate having at least one substantially planar surface, depositing a layer of mold protection material onto the at least one substantially planar surface, and etching a plurality of cavities into the at least one substantially planar surface through the mold protection layer.

1 . A method of forming a mold having a protective layer, the method comprising:
 forming a mold substrate having at least one substantially planar surface;   depositing a layer of mold protection material onto the at least one substantially planar surface; and   etching a plurality of cavities into the at least one substantially planar surface through the mold protection layer.   
     
     
         2 . The method of  claim 1 , further comprising:
 applying a lithographic film to the mold protection layer; and   patterning the lithographic film so as to define a plurality of cavity locations that correspond to the plurality of cavities.   
     
     
         3 . The method of  claim 2 , wherein etching a plurality of cavities into the at least one substantially planar surface includes etching the plurality of cavities into the at least one substantially planar surface at each cavity location. 
     
     
         4 . The method of  claim 2 , further comprising: removing the lithographic film from the mold protection layer prior to etching the plurality of cavities into the at least one substantially planar surface. 
     
     
         5 . The method of  claim 1 , further comprising:
 applying a lithographic film to the mold protection layer; and   etching the plurality of cavities into the at least one substantially planar surface through the lithographic film and the mold protection layer.   
     
     
         6 . The method of  claim 5 , further comprising: removing the lithographic film after the cavities are etched into the at least one substantially planar surface. 
     
     
         7 . The method of  claim 1 , wherein forming a mold substrate includes forming the mold substrate from borosilicate glass. 
     
     
         8 . The method of  claim 1 , wherein depositing a layer of mold protection material includes depositing at least one of SiC, Diamond like carbon (DLC), Si 3 N 4 , TiCN, TiN, Al 2 O 3  and PTFE 
     
     
         9 . The method of  claim 1 , further comprising: forming solder balls in the mold cavities. 
     
     
         10 . A method of protecting a mold having at least one substantially planar surface provided with a plurality of mold cavities, the method comprising:
 inserting a plurality of mandrels into respective ones of the plurality of mold cavities;   depositing a layer of mold protection material onto the at least one substantially planar surface and the plurality of mandrels; and   removing the plurality of mandrels from the mold substrate.   
     
     
         11 . The method of  claim 10 , wherein inserting a plurality of mandrels into respective ones of the plurality of mold cavities includes inserting a plurality of mandrels having a first end portion that extends into respective ones of the plurality of mold cavities and a second end portion that extends above the substantially planar surface. 
     
     
         12 . The method of  claim 11 , wherein depositing a layer of mold protection material onto the at least one substantially planar surface and the plurality of mandrels includes depositing the layer of mold protection material onto the second end portion of each of the plurality of mandrels. 
     
     
         13 . The method of  claim 12 , further comprising: removing the layer of mold protection material from the second end portion of each of the plurality of mandrels. 
     
     
         14 . The method of  claim 13 , wherein removing the layer of mold protection material from the second end portion of each of the plurality of mandrels includes polishing each of the plurality of mandrels such that the second end portion is substantially co-planar with the layer of mold protection material. 
     
     
         15 . The method of  claim 10 , wherein depositing a layer of mold protection material includes depositing at least one of SiC, Diamond like carbon (DLC), Si 3 N 4 , TiCN, TiN, Al 2 0 3  and PTFE. 
     
     
         16 . The method of  claim 10 , wherein inserting a plurality of mandrels into respective ones of the plurality of mold cavities includes inserting mandrels formed from a polymeric material. 
     
     
         17 . The method of  claim 16 , wherein inserting mandrels formed from a polymeric material includes inserting mandrels formed from polyimide. 
     
     
         18 . A mold for forming solder balls, the mold comprising:
 a substrate having a main body including a first substantially planar surface and an opposing second substantially planar surface, the substrate being formed from borosilicate glass (BSG);   a plurality of cavities formed in the first substantially planar surface, the plurality of cavities extending into the main body portion and stopping short of the second substantially planar surface; and   a protective layer formed on the first substantially planar surface, the protective layer being configured and disposed to prevent damage to the substrate.   
     
     
         19 . The mold according to  claim 18 , wherein the mold protective layer is formed from one of SiC, Diamond like carbon (DLC), Si 3 N 4 , TiCN, TiN, Al 2 O 3  and PTFE. 
     
     
         20 . The mold according to  claim 18  wherein the plurality of cavities are configured and disposed to produce a plurality of solder balls.