Processing substrates using a temporary carrier
View Patent ↗A technique comprising: securing a device substrate ( 8 ) to a carrier ( 1 ) using one or more adhesive elements ( 6 ); forming electronic elements ( 10 ) on the device substrate with the device substrate thus secured to the carrier; and thereafter reducing the adhesion strength of at least one of the one or more adhesive elements to facilitate the release of the substrate from the carrier.
1. A method, comprising:
securing a substrate to a carrier using one or more adhesive elements, wherein the device substrate exhibits a thermal co-efficient of expansion greater than that of the carrier;
forming electronic elements on the substrate with the substrate thus secured to the carrier,
wherein said forming electronic elements comprises controlling deposition of material and removal of deposited material on the basis of an expected position of the device substrate relative to the carrier,
wherein said forming electronic elements further comprises subjecting the device substrate to one or more temperature rises causing expansion of the device substrate, and
wherein the one or more adhesive elements have an internal cohesive strength sufficiently high to return the device substrate to a same position on the carrier upon reversal of the one or more temperature rises;
thereafter reducing the adhesion strength of at least one of the one or more adhesive elements to facilitate the release of the substrate from the carrier.
2. The method according to claim 1 , comprising: reducing the adhesion strength of at least one of the adhesive elements by heating.
3. The method according to claim 1 , wherein the substrate or device substrate is a flexible substrate, and the carrier is a glass carrier.
4. The method according to claim 1 , wherein the substrate or device substrate exhibits a co-efficient of thermal expansion of greater than about 10 ppm of expansion per degree C.
5. The method according to claim 1 , wherein the substrate or device substrate is more flexible than the carrier.
6. The method according to claim 1 , wherein the substrate or device substrate is secured to the carrier, as part of a sheet of substrate or device substrate material, providing a plurality of substrates or device substrates.
7. The method according to claim 1 , comprising: reducing the adhesion strength of at least one of the adhesive elements by irradiation.
8. The method according to claim 1 , wherein the substrate comprises an organic polymer substrate.
9. The method according to claim 1 , wherein the substrate comprises a flexible plastic substrate.
10. The method according to claim 1 , wherein forming electronic elements on the substrate comprises: sputter deposition and patterning of one or more metal layers.
11. The method according to claim 1 , wherein forming electronic elements on the substrate comprises depositing one or more materials from solution.
12. The method according to claim 1 , wherein forming electronic elements on the substrate comprises: defining source, drain and gate electrodes of a TFT array; forming semiconducting channels of the TFT array; and forming the gate dielectric of the TFT array.
13. The method according to claim 1 , wherein forming electronic elements on the substrate comprises: preventing the substrate from bubbling-up under low pressure/vacuum conditions.