Process for transfer imprinting
A process for transfer imprinting using a novel family of anti-sticking layers, such as for nanoimprint lithography processes, is described.
1. A transfer imprinting process comprising the following steps:
deposition of an anti-sticking layer on a template, optionally first treated by an adhesion primer (surface activation plasma), the anti-sticking layer comprising a homopolymer or a copolymer having at least one covalent bond that generates free radicals when the homopolyer or copolymer is activated thermally, by organic or inorganic redox, photochemically, by shearing, by plasma, or under the influence of ionizing radiation, the homopolymer or copolymer having a surface energy of greater than 5 mN/m, an elastic modulus E′ of greater than 1000 MPa at 25° C. or at the usage temperature as measured by dynamic mechanical analysis, and a weight-average molecular weight of greater than 500 g/mol,
activation of the covalent bond that generates free radicals thermally, by organic or inorganic redox, photochemically, by shearing, by plasma, or under the influence of ionizing radiation to form a film with a thickness of less than 50 nm on the template,
deposition or lamination of a polymer resin with a thickness ranging from 100 nm to 5 mm,
polymerization or cooling of the resin serving as imprint,
removing the imprint.
2. The process as claimed in claim 1 , wherein the covalent bonds that generate free radicals have a bonding energy of between 90 and 270 kJ/mol.
3. The process as claimed in claim 2 , wherein the homopolymer or the copolymer is prepared by controlled radical polymerization.
4. The process as claimed in claim 3 , wherein the homopolymer the copolymer is prepared by nitroxide-mediated radical polymerization.
5. The process as claimed in claim 4 , wherein the nitroxides correspond to the following formula:
in which the radical R L has a molar mass of greater than 15.0342.
6. The process as claimed in claim 5 , wherein the nitroxide is N-(tert-butyl)-1-diethylphosphono-2,2-dimethylpropyl nitroxide.
7. The use of the process as claimed in claim 1 in macroimprinting, microimprinting, nanoimprinting or stamping for lithography, microelectronics, photonics, optoelectronic applications, MEMS, NEMS, memories, microfluidics, biotechnology, biomedicine, self-cleaning surfaces, anti-reflective surfaces, displays (screens), transfer imprinting for replicating supports, audio or video, or objects for technical applications in leisure, sport, cars or aeronautics.