Transfer printing stamps and methods of stamp delamination
A stamp for micro-transfer printing includes a support having a support surface and posts disposed on the support surface. Each post has a proximal end in contact with the support and a distal end extending away from the support. The post has a post surface on the distal end. The post surface is a structured surface comprising spatially separated ridges that extend in a ridge direction entirely across the post surface and can be operable to form multiple delamination fronts when a first side of a micro-device is in contact with the post surface, a second side of the micro-device is in contact with a target surface of a target substrate, and the support is moved in a horizontal direction parallel to the target substrate surface. The post surface or ridges can be rectangular or non-rectangular with opposing edges having different lengths.
1. A stamp for micro-transfer printing, comprising:
a support having a support surface; and
a compressible post disposed on the support surface, the post comprising a distal end extending away from the support, the post having a post surface on the distal end,
wherein the post has a blind hole extending into an interior of the post from the post surface and a cutout extending from the blind hole through the post to an exterior surface of the post.
2. The stamp of claim 1 , wherein the post surface has a curved edge.
3. The stamp of claim 2 , wherein the post surface also has a straight edge.
4. The stamp of claim 2 , wherein the curved edge defines at least a portion of a circle.
5. The stamp of claim 1 , wherein at least a portion of the post surface is not parallel to the support surface.
6. The stamp of claim 1 , wherein the cutout is disposed along a line intersecting a center of the blind hole.
7. The stamp of claim 1 , wherein the cutout is disposed along a line that does not intersect a center of the blind hole.
8. The stamp of claim 1 , wherein the cutout is disposed along a line tangent to the blind hole.
9. The stamp of claim 1 , wherein the cutout is disposed along a line parallel to and in contact with an edge of the blind hole.
10. The stamp of claim 1 , wherein the post has a circular outer perimeter except for the cutout.
11. The stamp of claim 1 , wherein the blind hole has a circular cross section except for the cutout.
12. The stamp of claim 1 , wherein the blind hole has a circular cross section.
13. The stamp of claim 1 , wherein the blind hole extends through the post to the support surface.
14. The stamp of claim 1 , wherein the blind hole extends through the post less than entirely to the support surface.
15. The stamp of claim 1 , wherein the blind hole has a circular cross section and the post has a polygonal cross section.
16. The stamp of claim 1 , wherein the cutout is a channel.
17. The stamp of claim 1 , wherein the cutout is a tunnel.
18. The stamp of claim 1 , wherein the cutout is a slit.
19. The stamp of claim 18 , wherein the slit is shaped and sized to be open, thereby allowing gas to exit the blind hole, when the post is compressed and to be closed, thereby preventing gas from entering the blind hole, when the post is tensioned.
20. The stamp of claim 1 , wherein the cutout is shaped and sized to be open, thereby allowing gas to exit the blind hole, when the post is compressed and to be closed, thereby preventing gas from entering the blind hole, when the post is tensioned.
21. The stamp of claim 1 , wherein the cutout has a width and a height and the width is more than the height.
22. The stamp of claim 1 , wherein a height of the cutout is no more than 20% of a height of the post.