Patterning nano-scale patterns on a film comprising unzipping copolymers
The invention concerns a method for patterning a surface of a material. A substrate having a polymer film thereon is provided. The polymer is a selectively reactive polymer (e.g., thermodynamically unstable): it is able to unzip upon suitable stimulation. A probe is used to create patterns on the film. During the patterning, the film is locally stimulated for unzipping polymer chains. Hence, a basic idea is to provide a stimulus to the polymeric material, which in turn spontaneously decomposes e.g., into volatile constituents. For example, the film is thermally stimulated in order to break a single bond in a polymer chain, which is sufficient to trigger the decomposition of the entire polymer chain.
1. A method for patterning a material, comprising
providing a single layer of a polymer film, the polymer film comprising polymer chains of copolymers derived from two or more monomers, one of the monomers being a dialdehyde compound, whereby the polymer chains are able to unzip upon stimulation; and
patterning the film with a nano-scale dimensioned probe, by stimulating the film for triggering an unzipping reaction of polymer chains of the film, wherein the unzipping reaction produces volatiles to produce a patterned surface.
2. The method of claim 1 , wherein the polymer film provided comprises polymer chains for which an energetic or chemical modification event triggers the unzipping reaction and wherein patterning includes stimulating the film such that an energetic or chemical modification event occurs in at least one polymer chain.
3. The method of claim 1 , wherein the polymer film provided comprises polymer chains which are able to unzip upon breaking one chemical bond thereof and wherein patterning includes stimulating the film to break one bond of at least one polymer chain.
4. The method of claim 1 , wherein patterning includes having the probe provide an energy to the film to activate a chemical reaction involving a reactant in proximity with polymer chains, the chemical reaction allowing in turn for unzipping at least one polymer chain.
5. The method of claim 4 , wherein the reactant is an acid-generator.
6. The method of claim 5 , wherein the polymer film is provided with the acid-generator comprised therein, the acid-generator being activated during patterning.
7. The method of claim 5 , wherein the acid-generator is dispensed by the probe during patterning.
8. The method of claim 5 , wherein the acid-generator is a thermal-acid-generator, the thermal-acid-generator activated by the probe, heated during patterning.
9. The method of claim 5 , wherein the acid-generator is a photo-acid-generator, the photo-acid-generator activated by light during patterning.
10. The method of claim 1 , wherein said one of the monomers is a phthalaldehyde compound.
11. The method of claim 10 , wherein polymer chains of the polymer film provided comprises copolymers of phthalaldehyde compounds and benzaldehyde compounds.
12. The method of claim 11 , wherein at least some of the benzaldehyde compounds in the polymer chains of the polymer film provided are functionalized benzaldehyde compounds.
13. The method of claim 1 , wherein
the polymer chains of the polymer film provided globally derive from at least two compounds, one of the compounds being the dialdehyde compound,
and wherein at least some of the polymer chains of the polymer film provided comprise block copolymers of two or more homopolymer units, one of the homopolymer units deriving from the dialdehyde compound, whereby said at least some of the polymer chains are able to unzip upon stimulation.
14. The method of claim 13 , wherein said at least some of the polymer chains of the polymer film provided are ordered by way of another one of the homopolymer units, substantially more stable than said one of the homopolymer units upon stimulation.
15. The method of claim 14 , wherein the polymer chains in the polymer film provided have an average orientation with a non-zero component perpendicular to a plane of the polymer film.
16. The method of claim 15 , wherein the polymer chains in the polymer film provided are further ordered such that said at least some of the polymer chains that comprise block copolymers form a structured pattern in the plane of the polymer film.
17. The method of claim 15 , wherein the polymer chains in the polymer film provided are further ordered such that said at least some of the polymer chains that comprise block copolymers form a two-dimensional lattice in the plane of the polymer film.
18. The method of claim of claim 13 , wherein said one of the homopolymer units derives from a phthalaldehyde compound, whereas another one of the homopolymer units derives from a compound comprising a functional group capable of initiating a ring-closing polymerization of phthalaldehyde.