Non-contact transfer printing
A transfer printing process that exploits the mismatch in mechanical or thermo-mechanical response at the interface of a printable micro- or nano-device and a transfer stamp to drive the release of the device from the stamp and its non-contact transfer to a receiving substrate are provided. The resulting facile, pick-and-place process is demonstrated with the assembling of 3-D microdevices and the printing of GAN light-emitting diodes onto silicon and glass substrates. High speed photography is used to provide experimental evidence of thermo-mechanically driven release.
1. A method of transferring ink from a donor substrate to a receiving substrate, said method comprising:
providing a non-ablative transfer device having a transfer surface;
providing said donor substrate having a donor surface, said donor surface having ink thereon, wherein said ink is a micro-sized or nano-sized prefabricated electronic, optical, or electro-optical device or device component thereof;
contacting at least a portion of said transfer surface with at least a portion of said ink;
separating said transfer surface from said donor surface, wherein said ink is transferred from said donor surface to said transfer surface;
positioning said transfer surface having said ink disposed thereon into alignment with a receiving surface of said receiving substrate; and
actuating said transfer device, said ink, or both of said transfer device and said ink by generating a non-ablative force that releases at least a portion of said ink from said transfer surface, thereby transferring said ink to said receiving surface, wherein said step of actuating comprises mechanically stressing an interface between said transfer surface and said ink so as to cause delamination, thereby resulting in release of said ink.
2. The method of claim 1 , wherein a gap remains between said ink disposed on said transfer surface and said receiving surface during the actuation.
3. The method of claim 1 , wherein the non-ablative actuation force is generated while maintaining at least a portion of said gap.
4. The method of claim 1 , wherein said ink is in contact with the receiving surface during the actuation.
5. The method of claim 1 , wherein the actuation is electrostatic.
6. The method of claim 1 , wherein said step of actuating said transfer device uses a laser, a piezoelectric actuator, a gas source, a vacuum source, an electromagnetic source, an electrostatic source, an electronic source, a heat or thermal source, or a combination thereof.
7. The method of claim 6 , wherein said electrostatic source generates an applied electric field on said transfer surface, said ink disposed on said transfer surface, or both.
8. The method of claim 6 , wherein the actuation is thermal.
9. The method of claim 8 , wherein the thermal actuation is enabled by providing electromagnetic radiation.
10. The method of claim 9 , wherein the electromagnetic radiation is infrared radiation.
11. The method of claim 6 , wherein said heat source heats said transfer device, said ink, or both of said transfer device and said ink, thereby thermally actuating said transfer device, said ink, or both of said transfer device and said ink.
12. The method of claim 11 , wherein said heat source produces a temperature of said transfer surface selected from the range of 275 degrees C. to 325 degrees C.
13. The method of claim 6 , wherein said heat source produces a temperature gradient in said transfer device selected from the range of 10 4 degrees C. per cm to 10 5 degrees C. per cm.
14. The method of claim 1 , wherein the magnitude and spatial distribution of said force is selected so as to generate a separation energy between said ink and said transfer surface equal to or greater than 1 J/meter 2 .
15. The method of claim 1 , wherein the prefabricated device or device component is a semiconductor element.
16. The method of claim 1 , wherein the prefabricated device or device component is a light-emitting diode.
17. The method of claim 1 , wherein the prefabricated device or device component has a lateral dimension in the range of 100 nm to 100 microns.
18. The method of claim 1 , wherein the transfer device is an elastomeric stamp.
19. The method of claim 1 , wherein at least a portion of said transfer surface directly contacts at least a portion of said ink.
20. A method of transferring ink from a donor substrate to a receiving substrate, said method comprising:
providing a non-ablative transfer device having a transfer surface;
providing said donor substrate having a donor surface, said donor surface having ink thereon, wherein said ink is a micro-sized or nano-sized prefabricated electronic, optical, or electro-optical device or device component thereof;
contacting at least a portion of said transfer surface with at least a portion of said ink;
separating said transfer surface from said donor surface, wherein said ink is transferred from said donor surface to said transfer surface;
positioning said transfer surface having said ink disposed thereon into alignment with a receiving surface of said receiving substrate; and
actuating said transfer device, said ink, or both of said transfer device and said ink by generating a non-ablative force that releases at least a portion of said ink from said transfer surface, thereby transferring said ink to said receiving surface, wherein said step of actuating comprises electrostatic actuation.
21. The method of claim 20 , wherein a gap remains between said ink disposed on said transfer surface and said receiving surface during the actuation.
22. The method of claim 20 , wherein the non-ablative actuation force is generated while maintaining at least a portion of said gap.
23. The method of claim 20 , wherein said ink is in contact with the receiving surface during the actuation.
24. The method of claim 20 , wherein said electrostatic source generates an applied electric field on said transfer surface, said ink disposed on said transfer surface, or both.
25. The method of claim 20 , wherein the magnitude and spatial distribution of said force is selected so as to generate a separation energy between said ink and said transfer surface equal to or greater than 1 J/meter 2 .
26. The method of claim 20 , wherein the prefabricated device or device component is a semiconductor element.
27. The method of claim 20 , wherein the prefabricated device or device component is a light-emitting diode.
28. The method of claim 20 , wherein the prefabricated device or device component has a lateral dimension in the range of 100 nm to 100 microns.
29. The method of claim 20 , wherein the transfer device is an elastomeric stamp.
30. The method of claim 20 , wherein at least a portion of said transfer surface directly contacts at least a portion of said ink.