Method of manufacturing mold
In one embodiment, a method of manufacturing a mold includes: forming a first layer having an affinity to a second polymer on a substrate having an affinity to a first polymer; forming first and second openings in the first layer; filling a resist in the second openings and hardening the resist to obtain a hardened resist; and forming a second layer containing a block copolymer and causing it to self-assemble.
1. A method of manufacturing a mold, comprising:
forming a first layer, having a greater affinity to a second polymer than to a first polymer, on a substrate having a greater affinity to the first polymer than to the second polymer;
forming first openings and second openings in the first layer, the second openings being larger in size than the first openings;
applying a resist as a liquid on the first layer to fill the resist in the second openings, but not in the first openings;
hardening the resist filled in the second openings to obtain a hardened resist;
forming a second layer, containing a block copolymer having the first and second polymers, in the first openings and on the first layer;
causing the block copolymer to self-assemble to form a dot row arranged corresponding to the first openings and containing the first polymer;
removing the hardened resist;
processing the substrate using the dot row as a mask to form a mold having a first area with a shape corresponding to the dot row and a flat second area corresponding to the second openings; and
removing the first and second layers.
2. The method according to claim 1 ,
wherein the size of the first openings is 15 nm or less; and
wherein the resist includes a polymer having a molecular weight equal to or greater than 24000 and equal to or less than 60000.
3. The method according to claim 2 ,
wherein the size of the second openings is equal to or greater than four times the size of the first openings.
4. The method according to claim 1 ,
wherein the size of the first openings is 15 nm or less; and
wherein the resist has a viscosity equal to or greater than 1500 mPa·s and equal to or less than 10000 mPa·s.
5. The method according to claim 4 ,
wherein the size of the second openings is equal to or greater than four times the size of the first openings.
6. The method according to claim 1 ,
wherein the forming of the first openings and second openings, comprises:
forming a layer of a second resist on the first layer;
processing the layer of the second resist to have a shape corresponding to the first and second openings; and
etching the first layer using the processed layer of the second resist as a mask to form the first and second openings,
the method further comprising removing the processed layer of the second resist after the filling and hardening a resist.
7. The method according to claim 6 ,
wherein the processing of the layer of the second resist comprises:
pressing a mold having first and second projections corresponding to the first and second openings against the layer of the second resist; and
hardening the layer of the second resist against which the mold is pressed.
8. The method according to claim 6 ,
wherein a material of the second resist is novolac, PMMA, or PVA.
9. The method according to claim 8 , further comprising
removing the layer of the second resist by wet etching.
10. The method according to claim 1 ,
wherein the block copolymer is at least any one of PS (poly styrene)-PDMS (polydimethylsiloxane), PS-PMMA (polymenthyl methacrylate), PMMA-PMAPOSS (polymethacrylate containing polyhedral oligomeric silsesquioxane), and PS-PEO (polyethylene oxide).
11. The method according to claim 1 ,
wherein, in the forming of a dot row, the block copolymer self-assembles by annealing.