Apparatus and methods for micro-transfer-printing
In an aspect, a system and method for assembling a semiconductor device on a receiving surface of a destination substrate is disclosed. In another aspect, a system and method for assembling a semiconductor device on a destination substrate with topographic features is disclosed. In another aspect, a gravity-assisted separation system and method for printing semiconductor device is disclosed. In another aspect, various features of a transfer device for printing semiconductor devices are disclosed.
1. A method for assembling a semiconductor device on a receiving surface of a destination substrate by micro-transfer printing, the method comprising:
providing the semiconductor device formed on a native substrate, wherein the semiconductor device has a relatively low coefficient of thermal expansion;
contacting a top surface of the semiconductor device with a conformable transfer device comprising an elastomer stamp comprising a protruding post having a contact surface, wherein contact between the contact surface and the top surface of the semiconductor device at least temporarily binds the semiconductor device to the conformable transfer device, wherein the conformable transfer device has a relatively high coefficient of thermal expansion that is higher than the relatively low coefficient of thermal expansion of the semiconductor device;
separating the semiconductor device from the native substrate such that the contact surface of the conformable transfer device has the semiconductor device disposed thereon with the semiconductor device released from the native substrate;
contacting the semiconductor device disposed on the contact surface with the receiving surface of the destination substrate;
heating the destination substrate and the conformable transfer device to cause the conformable transfer device to expand more than the semiconductor device; and
separating the contact surface of the conformable transfer device from the semiconductor device, thereby micro-transfer printing the semiconductor device onto the receiving surface of the destination substrate.
2. The method of claim 1 , wherein the heat is provided by a heating element.
3. The method of claim 2 , wherein the heating element is disposed on a side of the destination substrate opposite the receiving surface.
4. The method of claim 2 , wherein the heating element a non-contact thermal source that does not make direct physical contact with the destination substrate.
5. The method of claim 1 , wherein the destination substrate is heated.
6. The method of claim 1 , wherein the heating element is a hotplate.
7. The method of claim 6 , wherein the hotplate is direct thermal contact with the destination substrate.
8. The method of claim 1 , wherein the destination substrate is heated to an equilibrium temperature prior to the printable semiconductor elements being transferred to the substrate.