IP Library Patent Application 18475370
Patent Application
App. No. 18/475,370

Semiconductor Die Bonding

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Quick Facts
Patent No.
US None
App. No.
18/475,370
Abstract

Die-attach materials for semiconductor device packages are provided. In one example, a semiconductor device package includes a submount. The semiconductor device package includes a semiconductor die comprising a wide bandgap semiconductor. The semiconductor device package includes a die-attach layer between the submount and the semiconductor die. The die-attach layer comprises gold (Au), tin (Sn), and cobalt (Co).

Claims (31)

1 . A semiconductor device package, comprising:

a submount;

a semiconductor die comprising a wide bandgap semiconductor;

a die-attach layer between the submount and the semiconductor die; and

wherein the die-attach layer comprises gold (Au), tin (Sn), and cobalt (Co).

2 . The semiconductor device package of claim 1 , wherein a concentration of cobalt in the die-attach layer is in a range of about 0.01% by weight to about 0.5% by weight.

3 . The semiconductor device package of claim 1 , wherein a concentration of cobalt in the die-attach layer is in a range of about 0.01% by weight to about 0.25% by weight.

4 . The semiconductor device package of claim 1 , wherein the die-attach layer comprises a eutectic alloy.

5 . The semiconductor device package of claim 1 , wherein the semiconductor device package comprises a protective layer on the die-attach layer.

6 . The semiconductor device package of claim 5 , wherein the protective layer comprises gold.

7 . The semiconductor device package of claim 1 , wherein the die-attach layer further comprises nickel (Ni), silver (Ag), copper (Cu), or aluminum (Al).

8 . The semiconductor device package of claim 1 , wherein the semiconductor device package comprises an adhesion layer.

9 . (canceled)

10 . The semiconductor device package of claim 8 , further comprising a diffusion barrier layer.

11 . The semiconductor device package of claim 10 , wherein the diffusion barrier layer comprises one or more of silver (Ag), nickel (Ni), palladium (Pd), or copper (Cu).

12 . The semiconductor device package of claim 1 , wherein a concentration of tin (Sn) in the die-attach layer is in a range of about 10% by weight to about 30% by weight.

13 . The semiconductor device package of claim 1 , wherein a concentration of gold (Au) in the die-attach layer is in a range of about 65% by weight to about 85% by weight.

14 . The semiconductor device package of claim 1 , wherein the die-attach layer is lead (Pb) free.

15 . The semiconductor device package of claim 1 , wherein the submount comprises copper (Cu).

16 . The semiconductor device package of claim 1 , wherein the submount comprises silver-plated copper (Cu).

17 . The semiconductor device package of claim 1 , wherein the submount comprises a lead frame, a clip structure, or a direct bonded copper (DBC) submount.

18 . The semiconductor device package of claim 1 , wherein the wide bandgap semiconductor comprises silicon carbide or a Group III nitride.

19 . (canceled)

20 . The semiconductor device package of claim 1 , wherein the semiconductor device package is a discrete power semiconductor package or a power module.

21 . (canceled)

22 . An attach material for attaching a wide bandgap semiconductor device to a submount, the attach material comprising a eutectic alloy, the eutectic alloy comprising gold (Au), tin (Sn), and cobalt (Co), wherein a concentration of cobalt in the eutectic alloy is in a range of about 0.01% by weight to about 0.5% by weight.

23 .- 30 . (canceled)

31 . A method for fabricating a semiconductor device package, comprising:

providing a die-attach material, the die-attach material comprising gold (Au), tin (Sn), and cobalt (Co), wherein a concentration of cobalt (Co) in the die-attach material is in a range of about 0.01% by weight to about 0.5% by weight; and

attaching a semiconductor die to a submount with the die-attach material.

32 .- 54 . (canceled)

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 27, 2023
From: DADVAND, AFSHIN; RICHTER, DANIEL GINN; BALARAMAN, DEVARAJAN
To: WOLFSPEED, INC.
Reel/Frame 065050/0750 →