Lamination and delamination technique for thin film processing
View Patent ↗This invention discloses a releasable adhesion layer having good adhesion during high temperature fabrication process in the absence of light, and delaminating at a lower temperature in the presence of light. One embodiment of this invention is a film of polymer whose thermal decomposition temperature changes drastically upon photoexposure. These materials, prior to photoexposure, can withstand temperatures in the range of approximately 200° C. to 300° C. without decomposition, yet decompose at around 100° C. with photoexposure. The releasable adhesion layer can be used in a thermal transfer element, sandwiching a donor substrate and a transfer layer having a plurality of multicomponent transfer units. In the absence of light, the releasable adhesion layer can sustain high temperature processing of these multicomponent transfer units. By photoexposing according to a pattern, the photoexposed multicomponent transfer units can be selectively released at a low temperature to transfer to a receptor.
1. A releasable adhesion layer comprising a polymer composition
having a low delamination temperature in the presence of light, whereby allowing the delamination of the releasable adhesion layer at low temperature; and
in the absence of light, maintaining good adhesion at a temperature higher than the delamination temperature, whereby permiting processing at a higher temperature;
wherein the main ingredient of the polymer composition is selected from a group consisting of phyhalaldehyde, polycarbonates and polyformals.
2. A releasable adhesion layer as in claim 1 wherein the polycarbonate comprises a plurality of a tertiary carbon next to one carbonate carbonyl per monomer unit.
3. A releasable adhesion layer as in claim 1 wherein the polyformal comprises a bisallylic diol or a bisbenzylic diol per monomer unit.
4. A releasable adhesion layer as in claim 1 wherein the polymer composition comprises an additive of an acid or base catalyst.
5. A releasable adhesion layer as in claim 1 wherein the light source is selected from a group consisting of visible light, ultraviolet light, and x-ray.
6. A thermal transfer element comprising:
a donor substrate;
a multicoinponent transfer layer to be transferred; and
a releasable adhesion layer disposed between the donor substrate and the multicomponent transfer layer, the releasable adhesion layer comprising a polymer composition
having a low delamination temperature in the presence of light, whereby allowing the selected delamination of the adhesion layer to transfer the multicomponent layer at a low delamination temperature; and
maintaining good adhesion between the donor substrate and the multicomponent transfer layer at a temperature higher than the delamination temperature in the absence of light, whereby permiting processing the multicomponent transfer layer at a temperature higher than the delamination temperature;
wherein the main ingredient of the polymer composition is selected from a group consisting of phthalaldehyde, polycarbonates and polyformals.
7. A thermal transfer element comprising:
a donor substrate;
a transfer layer comprising a plurality of multicomponent transfer units to be transferred; and
a releasable adhesion layer disposed between the donor substrate and the transfer layer, the releasable adhesion layer comprising a polymer composition
having a low delamination temperature in the presence of light, whereby allowing the delamination of the adhesion layer to transfer the selected multicomponent units by exposing the selected multicomponent units to light; and
maintaining good adhesion between the donor substrate and the multicomponent transfer layer at a temperature higher than the delamination temperature in the absence of light, whereby permiting processing the multicomponent transfer units at a temperature higher than the delamination temperature;
wherein the main ingredient of the polymer composition is selected from a group consisting of phthalaldehyde, polycarbonates and polyformals.
8. A thermal transfer element as in claim 7 wherein the polycarbonate comprises a plurality of a tertiary carbon next to one carbonate carbonyl per monomer unit.
9. A thermal transfer element as in claim 7 wherein the polyformal comprises a bisallylic diol or a bisbenzylic diol per monomer unit.
10. A thermal transfer element as in claim 7 wherein the polymer composition comprises an additive of an acid or base catalyst.
11. A thermal transfer element as in claim 7 wherein the light source is selected from a group consisting of visible light, ultraviolet light, and x-ray.
12. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises a plurality of contact pads.
13. A thermal transfer element as in claim 7 , further comprising an adhesive layer to facilitate adherence of the multicomponent transfer unit to the receptor.
14. A thermal transfer element as in claim 7 , wherein the donor substrate is a polymer substrate, a paper substrate, a glass substrate or a semiconductor substrate.
15. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises a plurality of layers.
16. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises a component in electronic circuitry.
17. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises an electronic device.
18. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises a thin film transistor device.
19. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises a semiconductor device.
20. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises a memory device.
21. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit comprises a display device.
22. A thermal transfer element as in claim 7 , wherein the donor substrate is transparent with respect to the light source.
23. A thermal transfer element as in claim 7 , wherein the multicomponent transfer unit is transparent with respect to the light source.