Laser lift-off masks

Patent metadata

Field	Value
Publication number	US-10811575-B2
Application number	US-201816049783-A
Country	US
Kind code	B2
Filing date	Jul 30, 2018
Priority date	Jul 30, 2018
Publication date	Oct 20, 2020
Grant date	Oct 20, 2020

Abstract

Techniques related to laser lift-off masks are disclosed. In some embodiments, masking material is applied to a substrate that is attached to a plurality of semiconductor device sets. More specifically, the masking material is applied to one or more regions of the substrate between the semiconductor device sets. When the semiconductor device sets are embedded in a filling material, the masking material may be situated between the substrate and the filling material. Thus, transmitting light through the substrate toward the semiconductor device sets causes the substrate to become detached from the semiconductor device sets. However, the light is at least partially occluded by the masking material.

First claim

What is claimed is:

1. A method comprising:
obtaining a plurality of semiconductor devices formed on a common substrate, the plurality of semiconductor devices including a first semiconductor device and a second semiconductor device spaced apart by a gap region of the substrate;
applying masking material over the gap region of the substrate;
embedding the plurality of semiconductor devices in a filling material; and
transmitting a first light through the substrate toward the plurality of semiconductor devices and the masking material, thereby causing the substrate to become detached from the plurality of semiconductor devices, wherein the first light is at least partially occluded by the masking material from reaching the filling material between the first semiconductor device and the second semiconductor device.

2. The method of claim 1 , wherein the masking material occludes the first light such that there is substantially no interaction between the first light and the filling material.

3. The method of claim 1 , wherein the masking material occludes the first light such that a reduced amount of heat results from interaction between the first light and the filling material.

4. The method of claim 1 , wherein embedding the plurality of semiconductor devices causes the masking material to be situated between the filling material and the substrate.

5. The method of claim 1 , further comprising:
prior to applying the masking material, embedding the plurality of semiconductor devices in a positive photoresist material;
transmitting a second light through the gap region of the substrate toward the positive photoresist material, thereby exposing one or more regions of the positive photoresist material to the second light; and
removing the one or more regions of the positive photoresist material.

6. The method of claim 5 , further comprising:
after applying the masking material, removing regions of the positive photoresist material that remain unexposed to the second light.

7. The method of claim 1 , further comprising:
prior to applying the masking material, embedding the plurality of semiconductor devices in a negative photoresist material;
transmitting a second light through the gap region of the substrate toward the negative photoresist material, thereby exposing one or more regions of the negative photoresist material to the second light; and
replacing, with a different material, regions of the negative photoresist material that remain unexposed to the second light; and
removing the one or more regions of the negative photoresist material.

8. The method of claim 7 , further comprising:
after applying the masking material, removing the different material.

9. The method of claim 1 , wherein the masking material is a metallic material that is applied based on a sputtering process.

10. A semiconductor device fabricated by a method comprising:
obtaining a plurality of semiconductor devices formed on a common substrate, the plurality of semiconductor devices including a first semiconductor device and a second semiconductor device spaced apart by a gap region of the substrate;
applying masking material over the gap region of the substrate;
embedding the plurality of semiconductor devices in a filling material; and
transmitting a first light through the substrate toward the plurality of semiconductor devices and the masking material, thereby causing the substrate to become detached from the plurality of semiconductor devices, wherein the first light is at least partially occluded by the masking material from reaching the filling material between the first semiconductor device and the second semiconductor device.

11. The semiconductor device of claim 10 , wherein the masking material occludes the first light such that there is substantially no interaction between the first light and the filling material.

12. The semiconductor device of claim 10 , wherein the masking material occludes the first light such that a reduced amount of heat results from interaction between the first light and the filling material.

13. The semiconductor device of claim 10 , wherein embedding the plurality of semiconductor devices causes the masking material to be situated between the filling material and the substrate.

14. The semiconductor device of claim 10 fabricated by the method, the method further comprising:
prior to applying the masking material, embedding the plurality of semiconductor devices in a positive photoresist material;
transmitting a second light through the gap region of the substrate toward the positive photoresist material, thereby exposing one or more regions of the positive photoresist material to the second light; and
removing the one or more regions of the positive photoresist material.

15. The semiconductor device of claim 14 fabricated by the method, the method further comprising:
after applying the masking material, removing regions of the positive photoresist material that remain unexposed to the second light.

16. The semiconductor device of claim 10 fabricated by the method, the method further comprising:
prior to applying the masking material, embedding the plurality of semiconductor devices in a negative photoresist material;
transmitting a second light through the gap region of the substrate toward the negative photoresist material, thereby exposing one or more regions of the negative photoresist material to the second light; and
replacing, with a different material, regions of the negative photoresist material that remain unexposed to the second light; and
removing the one or more regions of the negative photoresist material.

17. The semiconductor device of claim 16 fabricated by the method, the method further comprising:
after applying the masking material, removing the different material.

18. A non-transitory computer-readable storage medium storing processor-executable instructions for:
obtaining a plurality of semiconductor devices formed on a common substrate, the plurality of semiconductor devices including a first semiconductor device and a second semiconductor device spaced apart by a gap region of the substrate;
applying masking material over the gap region of the substrate;
embedding the plurality of semiconductor devices in a filling material; and
transmitting a first light through the substrate toward the plurality of semiconductor devices and the masking material, thereby causing the substrate to become detached from the plurality of semiconductor devices, wherein the first light is at least partially occluded by the masking material from reaching the filling material between the first semiconductor device and the second semiconductor device.

19. The non-transitory computer-readable storage medium of claim 18 , wherein the masking material occludes the first light such that there is substantially no interaction between the first light and the filling material.

20. The non-transitory computer-readable storage medium of claim 18 , wherein the masking material occludes the first light such that a reduced amount of heat results from interaction between the first light and the filling material.

Assignees

• Facebook Tech Llc

Inventors

• Brodoceanu Daniel
• Massoubre David
• Small James
• Torrents Abad Oscar
• Hughes Patrick Joseph

Classifications

• H10W74/014

  using batch processing · CPC title

• H10H20/0362

  of encapsulations · CPC title

• H10H20/854 Primary

  characterised by their material, e.g. epoxy or silicone resins · CPC title

• H10H20/018 Primary

  Bonding of wafers · CPC title

• H01L2933/005

  Electricity · mapped topic