Lithographic method for molding pattern with nanoscale depth

Abstract

The addition of thin coatings (less than and approaching monomolecular coatings) of persistent release materials comprising preferred compounds of the formula: RELEASE-M(X) n-1 — RELEASE-M(X) n-m-1 Q m , or RELEASE-M(OR) n-1 —, wherein RELEASE is a molecular chain of from 4 to 20 atoms in length, preferably from 6 to 16 atoms in length, which molecule has either polar or non-polar properties; M is a metal atom, semiconductor atom, or semimetal atom; X is halogen or cyano, especially Cl, F, or Br; Q is hydrogen or alkyl group; m is the number of Q groups; R is hydrogen, alkyl or phenyl, preferably hydrogen or alkyl of 1 to 4 carbon atoms; and; n is the valence −1 of M, and n-m-1 is at least 1 provides good release properties. The coated substrates are particularly good for a lithographic method and apparatus for creating ultra-fine (sub-25 nm) patterns in a thin film coated on a substrate is provided, in which a mold having at least one protruding feature is pressed into a thin film carried on a substrate. The protruding feature in the mold creates a recess of the thin film. The mold is removed from the film. The thin film then is processed such that the thin film in the recess is removed exposing the underlying substrate. Thus, the patterns in the mold is replaced in the thin film, completing the lithography. The patterns in the thin film will be, in subsequent processes, reproduced in the substrate or in another material which is added onto the substrate.

We claim:  
     
         1 . A method for forming a pattern on a moldable surface on a substrate comprising the steps of: 
 providing the substrate including the moldable surface;    providing a mold having a molding surface comprised of protruding features and recessed features wherein the mold depth between a protruding feature and a recessed feature is less than 250 nm;    urging together the molding surface and the moldable surface; and    separating the molding surface and the moldable surface to provide the moldable surface patterned with a feature having a depth in the range 5-250 nm.    
     
     
         2 . The method of  claim 1  wherein the moldable surface is molded to a pattern having at least one feature with minimum dimension of less than 200 nm and to a depth in the range 5-250 nm.  
     
     
         3 . The method of  claim 1  wherein the moldable surface comprises a polymer material.  
     
     
         4 . The method of  claim 1  further comprising the step of etching the moldable surface after separating the molding surface.  
     
     
         5 . The method of  claim 1  further comprising the step of applying a release material to the molding surface before urging together the molding surface and the moldable surface.  
     
     
         6 . The method of  claim 5  wherein the release material is bonded to the molding surface.  
     
     
         7 . The method of  claim 1  wherein the molding surface comprises a pattern for molding at least one feature with a minimum dimension of less than 25 nm.  
     
     
         8 . The method of  claim 1  wherein the molding surface comprises a material selected from the group consisting of metals, metal oxides, metal carbides and metal nitrides.  
     
     
         9 . The method of  claim 1  wherein the molding surface comprises a material selected from the group consisting of semimetals, semimetal oxides, semimetal carbides and semimetal nitrides.  
     
     
         10 . The method of  claim 1  wherein the molding surface comprises a material selected from the group consisting of polymers, semiconductors, photoconductors, ceramics and glasses.  
     
     
         11 . The method of  claim 1  wherein the molding surface comprises a plurality of layers.  
     
     
         12 . The method of  claim 1  wherein the substrate comprises a material selected from the group consisting of silicon, silicon nitride, and silicon carbide.  
     
     
         13 . The method of  claim 1  wherein the substrate comprises a material selected from the group consisting of doped semiconductor blends, organic photoconductors and inorganic photoconductors.  
     
     
         14 . The method of  claim 1  wherein urging the mold into the film comprises a process selected from the group consisting of impression molding, injection molding, powder molding, blow molding, casting, cast molding, vapor deposition molding and decomposition molding.  
     
     
         15 . The method of  claim 1  wherein the mold pattern comprises a uniform pattern.  
     
     
         16 . The method of  claim 1  wherein the mold pattern comprises a random pattern.  
     
     
         17 . The method of  claim 1  wherein the moldable surface comprises a molding composition that hardens by a process selected from the group consisting of cooling, polymerizing, chemically reacting, and irradiating.  
     
     
         18 . The method of  claim 1  wherein the moldable surface comprises a hardenable material selected from the group consisting of semiconductors, dielectric materials, photoresponsive materials, thermally responsive materials and electrically responsive materials.  
     
     
         19 . The method of  claim 1  wherein the moldable surface comprises a material selected from the group consisting of inorganic oxides, sulfides, halides, carbides and nitrides.  
     
     
         20 . The method of  claim 1  wherein the moldable surface comprises a material selected from the group consisting of rare earth oxides, sulfides, halides, carbides and nitrides.  
     
     
         21 . The method of  claim 1  wherein the moldable surface comprises a material selected from the group consisting of silicon compounds, cadmium compounds and zinc compounds.  
     
     
         22 . The method of  claim 1  wherein the moldable surface comprises a continuous coating or layer.  
     
     
         23 . The method of  claim 1  wherein the moldable surface comprises a discontinuous coating or layer.  
     
     
         24 . The method of  claim 1  wherein the moldable surface comprises a mixture, dispersion or blend.  
     
     
         25 . The method of  claim 1  wherein the moldable surface comprises a plurality of layers.  
     
     
         26 . The method of  claim 1  wherein the moldable surface comprises a thermoplastic material.  
     
     
         27 . The method of  claim 1  wherein the moldable surface comprises a hardenable or curable material.  
     
     
         28 . The method of  claim 1  wherein the moldable surface comprises a material which passes from a flowable state to a non-flowing state.  
     
     
         29 . The method of  claim 1  wherein the moldable surface comprises a material which passes from a flowable state to a non-flowing state upon a change in temperature, polymerization, curing or radiation.  
     
     
         30 . The method of  claim 1  including the step of softening the moldable surface to facilitate molding.  
     
     
         31 . The method of  claim 1  wherein the moldable surface is heated to soften the moldable surface.  
     
     
         32 . The method of  claim 1  wherein the moldable surface is cooled to harden the film.  
     
     
         33 . The method of  claim 1  wherein the moldable surface comprises a polymer having a glass transition temperature and the moldable surface is heated to a temperature above the glass transition temperature to flow into conformation with the features of the mold.  
     
     
         34 . The method of  claim 1  wherein the moldable surface comprises a sintered material.  
     
     
         35 . The method of  claim 1  wherein, prior to urging together the molding surface and the moldable surface, the moldable surface comprises powder.  
     
     
         36 . The method of  claim 1  wherein the moldable surface comprises a moldable polymer selected from the group consisting of acrylates, methacrylates, polycarbonates, polyvinyl resins, polyamides, polyurethanes, polysiloxanes, polyesters and polyethers.  
     
     
         37 . The method of  claim 1  wherein providing the substrate including the moldable surface comprises applying a moldable polymer on the substrate.  
     
     
         38 . The method of  claim 40  wherein the moldable polymer is applied by spin casting.  
     
     
         39 . The method of  claim 1  wherein the moldable surface comprises a sol.  
     
     
         40 . The method of  claim 1  wherein the moldable surface comprises a composite of a polymeric material and a non-polymeric material.  
     
     
         41 . The method of  claim 1  wherein the substrate and the mold act as plates for urging the mold into the moldable surface.  
     
     
         42 . The method of  claim 1  wherein the substrate and the mold are stiff to reduce bending.  
     
     
         43 . The method of  claim 1  including repeating the steps of providing the mold, urging together the molding surface and the moldable surface and separating the molding surface and the moldable surface.