Compliant micro device transfer head
A compliant micro device transfer head and head array are disclosed. In an embodiment a micro device transfer head includes a spring portion that is deflectable into a space between a base substrate and the spring portion.
1. A transfer head array comprising:
a base substrate; and
an array of transfer heads, each transfer head comprising:
a first spring arm extending from a first spring anchor to a spring platform;
a second spring arm extending from a second spring anchor to the spring platform; and
a mesa structure on the spring platform, wherein the spring platform is deflectable into a space between the spring platform and the base substrate.
2. The transfer head array of claim 1 , wherein the mesa structure generates a profile that protrudes away from the base substrate.
3. The transfer head array of claim 2 , wherein the mesa structure is formed integrally with the spring platform.
4. The transfer head array of claim 2 , wherein the first spring arm extends from a first corner of the spring platform to the first spring anchor.
5. The transfer head array of claim 4 , wherein the second spring arm extends from a second corner of the spring platform to the second spring anchor.
6. The transfer head array of claim 2 , wherein each of the first and second spring arms has a length of 8 to 30 μm.
7. The transfer head array of claim 2 , wherein each mesa structure includes a corresponding top surface, and the top surfaces are coplanar.
8. The transfer head array of claim 7 , further comprising a dielectric layer covering the top surface of each mesa structure.
9. The transfer head array of claim 2 , further comprising a first bend along a length of the first spring arm.
10. The transfer head array of claim 9 , further comprising a second bend along a length of the second spring arm.
11. The transfer head array of claim 2 , further comprising a second mesa structure on the spring platform, wherein the second mesa structure generates a profile that protrudes away from the base substrate.
12. The transfer head array of claim 11 , wherein the mesa structure and the second mesa structure are formed integrally with the spring platform.
13. The transfer head array of claim 11 , further comprising a dielectric layer covering the mesa structure and the second mesa structure of each transfer head.
14. The transfer head array of claim 11 , further comprising a first bend along a length of the first spring arm.
15. The transfer head array of claim 14 , further comprising a second bend along a length of the second spring arm.
16. The transfer head array of claim 15 , wherein the first spring arm extends from a first corner of the spring platform to the first spring anchor.
17. The transfer head array of claim 16 , wherein the second spring arm extends from a second corner of the spring platform to the second spring anchor.