Means for transferring a pattern to an object
A template ( 10 ) having a first surface ( 13, 14 ), usable for transferring a pattern of the first surface to an object ( 20 ) having a second surface ( 23 ) covered by a light-sensitive coating ( 22 ), by contacting the patterned first surface with the coating, wherein the template comprises a carrier base ( 11 ) of e.g. nickel, and a waveguide ( 14 ) is disposed on the carrier base at the first surface. The waveguide is devised to lead light therein, introduced at a radiation input, and to leak evanescent waves to portions ( 24 ) of the coating corresponding to said pattern. The template may also be devised with an opaque shield ( 15 ), disposed at the first surface over selected portions of the waveguide, which serves to define where the evanescent waves can leak to the coating. The invention also relates to a method and an apparatus for using the template, and a method for manufacturing it.
1. A template having a first surface, usable for transferring a pattern of the first surface to an object having a second surface covered by a light-sensitive coating, by contacting the patterned first surface with the coating, the template comprising a carrier base, and a waveguide layer disposed on the carrier base at the first surface, the waveguide layer being devised to lead light therein and to leak evanescent waves to portions of the coating corresponding to said pattern, and wherein the first surface comprises a structure with projections and recesses, on which structure the waveguide layer is disposed, the template being adapted for pressing the projections into the coating such that the coating fills up the recesses.
2. The template of claim 1 , wherein an opaque shield is disposed at the first surface over selected portions of the waveguide layer.
3. The template as recited in claim 2 , characterised in that the opaque shield forms the pattern of the first surface.
4. The template as recited in claim 1 , wherein an opaque shield is disposed on the waveguide layer at the recesses.
5. The template of claim 1 , wherein the light-sensitive coating is made of a negative resist material.
6. The template of claim 1 , wherein the light-sensitive coating is made of a positive resist material.
7. The template as recited in claim 1 , wherein the carrier base is made of a metal material.
8. The template as recited in claim 7 , characterised in that the carrier base is made of nickel.
9. The template of claim 1 , wherein the waveguide layer is made of a material selected from SiO 2 , Si 3 N 4 , diamond, sapphire or ITO.
10. The template of claim 1 , wherein the waveguide layer has a thickness of not more than 5 nm.
11. An apparatus for transferring a pattern from a template, the apparatus comprising the template of claim 1 ; a light source for exposing the coating to radiation; means for exposing the coating to evanescent waves from the waveguide layer to affect a property of selected portions of the coating; and means for pressing the protections into the coating such that the coating fills up the recesses.
12. The apparatus as recited in claim 11 , characterised in that the light source is devised to introduce light into the waveguide layer at a periphery portion of the template.
13. The apparatus as recited in claim 12 , characterised in that the light source is ring-shaped.
14. The apparatus as recited in claim 11 , characterised in that the light source is devised to emit UV radiation.
15. The apparatus as recited in claim 11 , characterised in that the light source comprises an array of UV diodes.
16. The apparatus as recited in claim 11 , characterised in that a lens arrangement is devised to couple radiation from the light source to a radiation input of the waveguide layer.
17. The apparatus as recited in claim 11 , characterised in that an optical fibre arrangement is devised to couple radiation from the light source to radiation input of the waveguide light source.
18. A method for transferring a pattern from a template having a patterned first surface, to an object having a second surface covered by a light-sensitive coating, wherein the first surface comprises a structure with protections and recesses, on which structure a waveguide layer is disposed, the method comprising the steps of:
placing the patterned first surface in contact with the coating;
introducing light into the waveguide layer disposed at the first surface;
exposing the coating to evanescent waves from the waveguide layer to affect a property of selected portions of the coating, and
pressing the projections into the coating such that the coating fills up the recesses.
19. The method as recited in claim 18 , further comprising the steps of: separating the template from the object; removing material from the coating in a development process dependent on said property, to create a three-dimensional structure corresponding to the selected portions in the coating.
20. The method as recited in claim 19 , further comprising the step of: exposing selected areas of the second surface in the development process.
21. The method as recited in claim 18 , wherein the light-sensitive coating is made of a negative resist material, the method further comprising the steps of: hardening the selected portions by the exposure to the evanescent waves; and removing non-hardened portions in a development process.
22. The method as recited in claim 18 , wherein the light-sensitive coating is made of a positive resist material, the method further comprising the steps of: making the selected portions soluble in a development process, by the exposure to the evanescent waves; and removing the soluble portions in a development process.
23. The method as recited in claim 18 , wherein an opaque shield is disposed on the first surface over the waveguide, the method further comprising the step of: guiding the evanescent waves from the waveguide layer through apertures in the opaque shield to the selected portions of the coating.
24. The method as recited in claim 18 , wherein UV radiation is introduced in the waveguide layer.