Method for making patterns on the surface of a substrate using block copolymers
A method for making patterns on the surface of a substrate by graphoepitaxy, includes depositing a layer of resin on the surface of the substrate; making patterns in the resin on the surface of a substrate; curing the patterns in the resin by producing a layer of amorphous carbon on the surface of the patterns in the resin; depositing a layer of statistical copolymer after curing the patterns in the resin; grafting the layer of statistical copolymer onto the patterns in the resin by annealing; and depositing a layer of a block copolymer into the spaces defined by the patterns in the resin after curing the patterns and the grafting of the layer of statistical copolymer.
1. Method for making patterns on the surface of a substrate by graphoepitaxy comprising:
depositing a layer of resin on the surface of the substrate;
making patterns in the resin on the surface of the substrate;
producing a layer of amorphous carbon on the surface of the patterns in the resin;
depositing a layer of random copolymer after producing the layer of amorphous carbon on the surface of the patterns in the resin;
grafting the layer of random copolymer onto the patterns in the resin, between the patterns in the resin and onto sides of the patterns in the resin, by annealing;
depositing a layer of block copolymer into spaces defined by the patterns in the resin after the grafting.
2. Method according to claim 1 , wherein the patterns in the resin are cured by treating the patterns in the resin by a gaseous plasma.
3. Method according to claim 2 , wherein the gaseous plasma is a HBr plasma.
4. Method according to claim 1 , wherein the patterns in the resin are cured by bombarding the patterns in the resin with ions.
5. Method according to claim 4 , wherein the ions are helium or argon ions.
6. Method according to claim 1 , wherein the patterns in the resin are formed by optical lithography of the layer of resin.
7. Method according to claim 1 , further comprising depositing an antireflective layer on the surface of the substrate.
8. Method according to claim 1 further comprising, following the depositing of the layer of block copolymer, reorganising the layer of block copolymer by annealing.
9. Method according to claim 8 , further comprising, following the reorganising, eliminating one of the phases of the layer of reorganised block copolymer.
10. Method according to claim 1 wherein the random copolymer is composed of the same monomers as those which compose the block copolymer.
11. Method according to claim 1 wherein the block copolymer is a lamellar block copolymer.
12. Method according to claim 1 , wherein the block copolymer is a cylindrical block copolymer.
13. Method according to claim 1 , wherein the layer of random copolymer is grafted onto a top of the patterns in the resin.