IP Library Granted Patent US 12,525,457
Granted Patent B2
US 12,525,457 · App. 18/734,796 · Granted Jan 13, 2026

Surface processing of semiconductor workpieces

Inventors: Nolan David Germano (Raleigh, NC); Emma Elizabeth Stone (Durham, NC)
Assignee: WOLFSPEED, INC.
H01L21/304B24B49/03B24B49/05H01L22/12H01L2221/68331
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Quick Facts
Patent No.
US 12,525,457
App. No.
18/734,796
Granted
Jan 13, 2026
Kind
B2
Abstract

An example method includes obtaining data indicative of a workpiece processing parameter. In some implementations, the example method includes determining a grinding depth for a semiconductor workpiece based at least in part on the data indicative of the workpiece processing parameter. In some implementations, the example method includes performing a grinding operation to remove material from the semiconductor workpiece to reduce a thickness of the semiconductor workpiece by the grinding depth.

Claims (26)

1 . A method, comprising:

obtaining data indicative of a workpiece removal parameter, the workpiece removal parameter indicative of processing information used to separate semiconductor workpieces from a boule;

performing a grinding operation to remove material from a first semiconductor workpiece removed from the boule to reduce a thickness of the first semiconductor workpiece by a first grind depth;

obtaining an image of the first semiconductor workpiece after the grinding operation; and

determining, based on the image and the data indicative of the workpiece removal parameter, second grind depth for a second semiconductor workpiece, the second semiconductor workpiece removed from the boule after the first semiconductor workpiece;

wherein the second grind depth is different than the first grind depth.

2 . The method of claim 1 , wherein the semiconductor workpiece is a semiconductor wafer.

3 . The method of claim 1 , wherein the workpiece wafer removal parameter comprises at least one of a wafer separation type, a laser power, a position of the semiconductor wafer within a semiconductor boule, or a material type of the semiconductor wafer.

4 . The method of claim 3 , wherein the data indicative of the workpiece removal parameter further comprises a predetermined value.

5 . The method of claim 4 , wherein determining the grinding depth for the semiconductor workpiece comprises:

determining a first adjustment to the first grinding depth based at least in part on the predetermined value; and

determining a second adjustment to the first grinding depth based at least in part on a boule image.

6 . The method of claim 5 , wherein the first adjustment is greater than the second adjustment.

7 . The method of claim 1 , wherein the first grind depth is determined using a model, the model being a machine-learned model.

8 . The method of claim 7 , wherein the machine-learned model is trained to provide the output based at least in part on a boule image.

9 . The method of claim 1 , wherein the first grind depth is less than the second grind depth.

10 . A system for grinding semiconductor workpieces, the system comprising:

a grinding surface operable to remove semiconductor material from a surface of a semiconductor workpiece;

a translation stage operable to impart relative motion between the grinding surface and the semiconductor workpiece;

an image-capturing device; and

control circuitry configured to perform operations, the operations comprising:

determining a first grinding depth for a first semiconductor workpiece based at least in part on the data indicative of a workpiece removal parameter, the workpiece removal parameter indicative of processing information used to separate semiconductor workpieces from a boule;

controlling the grinding surface to remove the semiconductor material from the first semiconductor workpiece to reduce a thickness of the first semiconductor workpiece by the first grinding depth;

obtaining an image of the first semiconductor workpiece after the grinding operation; and

determining, based on the image and the data indicative of the workpiece removal parameter, a second grinding depth for a second semiconductor workpiece, the second semiconductor workpiece removed from the boule after the first semiconductor workpiece;

wherein the second grinding depth is different than the first grinding depth.

Assignments (8)
NOTICE OF GRANT OF SECURITY INTEREST IN INTELLECTUAL PROPERTY Recorded Mar 26, 2026
From: WOLFSPEED, INC.
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 075280/0919 →
RELEASE OF SECURITY INTEREST IN INTELLECTUAL PROPERTY COLLATERAL AT REEL/FRAME NO. 69180/0437 Recorded Sep 30, 2025
From: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
To: WOLFSPEED, INC.
Reel/Frame 072989/0088 →
NOTICE OF GRANT OF SECURITY INTEREST IN INTELLECTUAL PROPERTY Recorded Sep 30, 2025
From: WOLFSPEED, INC.
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 072992/0113 →
NOTICE OF GRANT OF SECURITY INTEREST IN INTELLECTUAL PROPERTY Recorded Sep 30, 2025
From: WOLFSPEED, INC.
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 072992/0381 →
NOTICE OF GRANT OF SECURITY INTEREST IN INTELLECTUAL PROPERTY Recorded Sep 30, 2025
From: WOLFSPEED, INC.
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 072992/0467 →
NOTICE OF GRANT OF SECURITY INTEREST IN INTELLECTUAL PROPERTY Recorded Sep 30, 2025
From: WOLFSPEED, INC.
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 072992/0588 →
SECURITY INTEREST Recorded Oct 17, 2024
From: WOLFSPEED, INC.
To: U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 069180/0437 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 5, 2024
From: GERMANO, NOLAN DAVID; STONE, EMMA ELIZABETH
To: WOLFSPEED, INC.
Reel/Frame 068501/0116 →
Continuity (1)
Related Publication 20250379058A1 · Dec 11, 2025
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