Nanoimprint lithography having solvent-free liquid polymer resist

Abstract

A polymer resist having a good flow is used in a nanoimprint lithography. A residual layer remained is thus thinner. Hence, a time spent for etching the residual layer is reduced. And a pattern obtained after the nanoimprint lithography will not be ruined because of a long-time etching. Nevertheless, the present invention can be applied on a hard substrate, like a silicon chip, or a soft substrate, like PET.

1 . A nanoimprint lithography (NIL) having a solvent-free liquid polymer resist, comprising steps of: 
 (a) mixing at least one polymer material, at least one monomer and a thermal initiator to obtain a polymer resist;    (b) deposing said polymer resist on a substrate to obtain a polymer resist layer through a method selected from a group consisting of coating and dropping;    (c) applying a pressure to said polymer resist layer to process a NIL through an imprint machine under a coordination of a mold having a space pattern;    (d) heating said imprint machine to a first temperature while remaining said pressure;    (e) after said polymer resist layer is hardened, cooling down to a second temperature and releasing said mold from said polymer resist layer to obtain a polymer imprinted pattern; and    (f) etching a residual layer of a sunken area being remained on said polymer imprinted pattern.    
     
     
         2 . The NIL according to  claim 1 , 
 wherein said polymer resist is a solvent-free liquid polymer resist.    
     
     
         3 . The NIL according to  claim 1 , 
 wherein said monomer is selected from a group consisting of a monofunctional group acrylic monomer having single double bond, a bifunctional group acrylic monomer having dual double bond, and a multi-functional group acrylic monomer having multi-double bond.    
     
     
         12 . The NIL according to  claim 3 , 
 wherein said acrylic monomer is selected from a group consisting of methyl methacrylate (MMA) and nomal-butylacrylate (n-BA).    
     
     
         4 . The NIL according to  claim 1 , 
 wherein said polymer material is selected from a group consisting of a thermoplastic polymer, an oligomer having single double bond, and an oligomer having dual double bond.    
     
     
         5 . The NIL according to  claim 1 , 
 wherein said thermal initiator is 2,2′-azobisisobutyronitrile (AIBN).    
     
     
         6 . The NIL according to  claim 1 , 
 wherein said substrate is a transparent soft substrate selected from a group consisting of polyethylene terephthalate (PET) and polyethylene terephthalate/indium tin oxide (PET/ITO).    
     
     
         7 . The NIL according to  claim 1 , 
 wherein said substrate is selected from a group consisting of a silicon chip and a glass.    
     
     
         8 . The NIL according to  claim 1 , 
 wherein said pressure is between 2 kilograms per square centimeter (Kg/cm 2 ) and 60 Kg/cm 2 .    
     
     
         9 . The NIL according to  claim 1 , 
 wherein said first temperature is between 70 Celsius degrees (° C.) and 150° C.    
     
     
         10 . The NIL according to  claim 1 , 
 wherein said second temperature is between 15° C. and 25° C.    
     
     
         11 . The NIL according to  claim 1 , 
 wherein said polymer resist in step 
 (a) is obtained through steps of:  
 (a1) mixing at least one polymer material and at least one monomer to obtain a mixture;  
 (a2) after no polymer material powder and no polymer material particles are remained in said mixture, adding a thermal initiator to said mixture; and  
 (a3) stirring said mixture under a third temperature until said polymer material, said monomer and said thermal initiator are completely solved.  
   
     
     
         13 . The NIL according to  claim 1 , 
 wherein said third temperature is lower than 25° C.    
     
     
         14 . The NIL according to  claim 1 , 
 wherein said step (c) together with said step (d) is done through injection molding.