Method of transferring devices by lateral etching of a sacrificial layer
The present invention relates to a method for transferring devices. A sacrificing layer is positioned before the devices are manufactured, and a transition substrate is pasted on the devices. Then, a method for lateral wet etching or a method for lateral wet etching with mechanical stripping is applied for removing or stripping the sacrificing layer so as to separate the devices and a substrate. The separated devices are transferred to the transition substrate so as to meet the requirements for various products and applications.
1. A method of transferring devices, comprising steps of:
(a) forming a sacrificial layer on a substrate, wherein the sacrificial layer is made of metal;
(b) forming a buffer layer on the sacrificial layer;
(c) forming devices on the buffer layer;
(d) forming a plurality of etching channels in the buffer layer and between the devices, and the etching channels expose a portion of the sacrificial layer;
(e) utilizing the etching channels to remove parts of the sacrificial layer by lateral etching, and a plurality of pillars of the sacrificial layer is remained;
(f) pasting a first transition substrate on the devices; and
(g) separating the substrate from the buffer layer by removing or stripping off the pillars of the sacrificial layer, the devices are transferred.
2. The method of claim 1 , wherein the buffer layer is made of silicon oxide or silicon nitride.
3. The method claim 1 , wherein in the step (e) is processed by passing an etching solution for the sacrificial layer through the etching channels.
4. The method of claim 1 , wherein in the step (g) further comprises:
removing the pillars of the sacrificial layer by lateral wet etching.
5. The method of claim 1 , wherein in the step (g) further comprises:
stripping off the pillars of the sacrificial layer by mechanical stripping.
6. The method of claim 1 , wherein after the step (g) further comprises:
pasting a second transition substrate on the buffer layer; and
removing the first transition substrate.
7. A method of transferring devices, comprising:
(a) forming a sacrificial layer on a substrate, and the sacrificial layer has a plurality of holes exposing parts of the substrate;
(b) forming a buffer layer to cover the sacrificial layer and fill the plurality of holes to form a plurality of pillars;
(c) forming the devices on the buffer layer;
(d) forming a plurality of etching channels in the buffer layer and between the devices, and the etching channels expose a portion of the sacrificial layer;
(e) utilizing the etching channels to remove the sacrificial layer fully by lateral etching, and the pillars of the buffer layer is remained;
(f) pasting a first transition substrate on the devices; and
(g) separating the substrate from the buffer layer by removing or stripping off the pillars of the buffer layer, the devices are transferred.
8. The method of claim 7 , wherein the sacrificial layer is made of metal.
9. The method of claim 7 , wherein the buffer layer is made of silicon oxide or silicon nitride.
10. The method of claim 7 , wherein the plurality of pillars is used to support the devices.
11. The method of claim 7 , wherein the etching channels are positioned on the sacrificial layer.
12. The method of claim 7 , wherein the step (e) is processed by passing an etching solution for the sacrificial layer through the etching channels.
13. The method of claim 7 , wherein in the step (g) further comprises:
removing the pillars of the buffer layer by lateral wet etching.
14. The method of claim 7 , wherein in the step (g) further comprises:
stripping off the pillars of the buffer layer by mechanical stripping.
15. The method of claim 7 , wherein after the step (g) further comprises:
pasting a second transition substrate on the buffer layer; and
removing the first transition substrate.