Alignment process for the transfer setup

Patent metadata

Field	Value
Publication number	US-12237234-B2
Application number	US-202017613259-A
Country	US
Kind code	B2
Filing date	May 22, 2020
Priority date	May 22, 2019
Publication date	Feb 25, 2025
Grant date	Feb 25, 2025

Abstract

A method of aligning a first substrate and a second substrate comprises positioning the first substrate having at least a first alignment mark in close proximity to the second substrate having at least a second alignment mark, measuring an alignment value between the first and second alignment marks of both the first and second substrate; and adjusting the position of the first substrate and the second substrate based on the measured alignment value.

First claim

The invention claimed is:

1. A method of aligning a first substrate and a second substrate comprising:
positioning the first substrate in close proximity to the second substrate, wherein the first substrate has at least a first alignment mark comprising four plates and wherein the second substrate has at least a second alignment mark comprising a single plate, and wherein the close proximity is a proximity at which the first alignment mark and the second alignment mark form a capacitance;
measuring an alignment value between the first and second alignment marks of both the first and second substrate; and
adjusting the position of the first substrate and the second substrate based on the measured alignment value.

2. The method of claim 1 , wherein a detector and signal source are on the first substrate and a transfer medium is formed on the second substrate.

3. The method of claim 2 , wherein as the signal source and detector are aligned with the transfer medium, a signal detected by the detector is maximized.

4. The method of claim 3 , wherein the transfer medium can be a conductive trace.

5. The method of claim 3 , wherein a combination of signal, detector and transfer medium can be in different orientations to assist in different misalignment signals.

6. The method of claim 1 , wherein two detectors and signal source are on the first substrate and a transfer medium is formed on the second substrate.

7. The method of claim 6 , wherein as the signal source and detector are aligned with the transfer medium, a signal passed to the transfer medium is detected by the two detectors.

8. The method of claim 7 , wherein the signal received by both detectors is equalized and maximized such that each detector, signal and medium set assists in offset and rotation misalignment.

9. The method of claim 8 , wherein more sets can assist in fine tuning misalignment information.

10. The method of claim 8 , wherein a misalignment information is used to align substrates.

11. The method of claim 8 , where in a size of the transfer medium, the detector and the signal is used to define an alignment accuracy.

12. The method of claim 8 , where in a size of the detector and the signal is used to define an alignment accuracy.

13. The method of claim 11 , wherein if the size of the transfer medium is larger than the detector or the signal then coarse alignment is addressed.

14. The method of claim 11 , wherein if the size of the transfer medium is the same as the detector or the signal then fine alignment is addressed.

15. The method of claim 1 , wherein measuring the alignment value between the alignment marks of both the first and second substrate comprising:
extracting the alignment value at a current position of the substrates; and
moving the substrates with respect to each other in different directions to measure a change in the alignment value.

16. The method of claim 15 , further comprising:
comparing the alignment value to the change in the alignment value; and
adjusting the position of the first substrate and the second substrate based on comparing.

17. The method of claim 15 , wherein adjusting the position of the first substrate and the second substrate based on comparing comprises one of: maximizing, minimizing or equalizing the alignment value for each alignment mark.

18. The method of claim 1 , wherein the four plates and the single plate are metal plates or capacitive plates.

19. The method of claim 18 , wherein the alignment value is maximized between the capacitive plates.

20. The method of claim 1 , wherein the first alignment mark comprises charge trapped on a surface of the first substrate and the second alignment mark on the second substrate comprises a metal plate on a surface of the second substrate.

21. The method of claim 1 , wherein the first alignment mark comprises a shield plate on a surface of the first substrate and the alignment mark on the second substrate comprises a receiver plate on the second substrate.

22. The method of claim 21 , wherein the alignment value is minimized between the shield plate and the receiver plate.

23. The method of claim 1 , wherein the single plate is a metal plate.

24. The method of claim 23 , wherein the alignment value for the four plates and the single plate is equalized by moving one of the first substrate or the second substrate.

25. The method of claim 1 , wherein the alignment value comprises one of: a capacitance value, inductance value, a charge value, or another electrical signal value between the substrates.

Assignees

• Vuereal Inc
• VueReal

Inventors

• Chaji Gholamreza

Classifications

• H10W90/00

  Package configurations · CPC title

• H10W46/301

  for alignment · CPC title

• H10W46/607

  Located on parts of packages, e.g. on encapsulations or on package substrates · CPC title

• H10W46/00

  Marks applied to devices, e.g. for alignment or identification · CPC title

• H10P74/23 Primary

  characterised by multiple measurements, corrections, marking or sorting processes · CPC title