IP Library Granted Patent US 12,506,048
Granted Patent B2
US 12,506,048 · App. 17/888,845 · Granted Dec 23, 2025

Bifacial semiconductor wafer

Inventors: Lei Shi (Shanghai, CN); Cong Zhang (Shanghai, CN); Chin-Tien Chiu (Shanghai, CN)
Assignee: Sandisk Technologies, Inc.
H01L23/481H01L24/02H01L2224/02331H01L2224/02372H01L2224/02373
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Quick Facts
Patent No.
US 12,506,048
App. No.
17/888,845
Granted
Dec 23, 2025
Kind
B2
Abstract

A semiconductor device having one or more bifacial semiconductor wafers. The bifacial semiconductor wafer includes a first array of semiconductor dies on a first planar surface and a second array of semiconductor dies on a second planar surface that is opposite the first planar surface. The first array of semiconductor dies are electrically coupled via a first redistribution layer and the second array of semiconductor dies are electrically coupled via a second redistribution layer. One or more through silicon vias electrically couple the first array of semiconductor dies with the second array of semiconductor dies.

Claims (25)

1 . A semiconductor device, comprising:

a bifacial semiconductor wafer having a first planar surface and a second planar surface opposite the first planar surface;

a first plurality of semiconductor dies fabricated onto the first planar surface;

a second plurality of semiconductor dies fabricated onto the second planar surface; and

a plurality of through silicon vias electrically coupling the first plurality of semiconductor dies on the first planar surface with the second plurality of semiconductor dies on the second planar surface.

2 . The semiconductor device of claim 1 , further comprising a first redistribution layer associated with the first plurality of semiconductor dies, the first redistribution layer enabling communication between the first plurality of semiconductor dies.

3 . The semiconductor device of claim 1 , further comprising a second redistribution layer associated with the second plurality of semiconductor dies, the second redistribution layer enabling communication between the second plurality of semiconductor dies.

4 . The semiconductor device of claim 1 , wherein the bifacial semiconductor wafer is a first bifacial semiconductor wafer and wherein the semiconductor device further comprises:

a second bifacial semiconductor wafer having a first planar surface and a second planar surface opposite the first planar surface;

a first plurality of semiconductor dies fabricated onto the first planar surface;

a second plurality of semiconductor dies fabricated onto the second planar surface; and

a plurality of through silicon vias electrically coupling the first plurality of semiconductor dies on the first planar surface with the second plurality of semiconductor dies on the second planar surface.

5 . The semiconductor device of claim 4 , wherein the first bifacial semiconductor wafer is electrically coupled to the second bifacial semiconductor wafer.

6 . The semiconductor device of claim 5 , wherein the first bifacial semiconductor wafer is electrically coupled to the second bifacial semiconductor wafer via a copper to copper bond between the first bifacial semiconductor wafer and the second bifacial semiconductor wafer.

7 . The semiconductor device of claim 5 , wherein the first bifacial semiconductor wafer is electrically coupled to the second bifacial semiconductor wafer via one or more solder bumps.

8 . The semiconductor device of claim 5 , further comprising a molding compound disposed between a gap that is formed between the first bifacial semiconductor wafer and the second bifacial semiconductor wafer when the first bifacial semiconductor wafer and the second bifacial semiconductor wafer are electrically coupled.

9 . The semiconductor device of claim 1 , wherein the second planar surface is electrically coupled to a substrate.

10 . A semiconductor device, comprising:

a first bifacial semiconductor wafer having a first circuit layer fabricated onto a first planar surface and a second circuit layer fabricated onto a second planar surface opposite the first planar surface, the first circuit layer being electrically coupled to the second circuit layer; and

a second bifacial semiconductor wafer electrically coupled to the first bifacial semiconductor wafer, the second bifacial semiconductor wafer having a first circuit layer fabricated onto a first planar surface and a second circuit layer fabricated onto a second planar surface opposite the first planar surface, the first circuit layer of the second bifacial semiconductor wafer being electrically coupled to the second circuit layer of the first bifacial semiconductor wafer.

11 . The semiconductor device of claim 10 , further comprising a first redistribution layer associated with the first circuit layer and a second redistribution layer associated with the second circuit layer on the first bifacial semiconductor wafer.

12 . The semiconductor device of claim 10 , further comprising one or more through silicon vias for electrically coupling the first circuit layer on the first bifacial semiconductor wafer with the second circuit layer on the first bifacial semiconductor wafer.

13 . The semiconductor device of claim 10 , wherein the first bifacial semiconductor wafer is electrically coupled to the second bifacial semiconductor wafer using a copper to copper bond.

14 . The semiconductor device of claim 10 , further comprising a substrate electrically coupled to the second circuit layer of the second bifacial semiconductor wafer.

15 . The semiconductor device of claim 10 , wherein an outer edge of the first bifacial semiconductor wafer is substantially aligned with an outer edge of the second bifacial semiconductor wafer.

Assignments (9)
NUNC PRO TUNC ASSIGNMENT Recorded Nov 25, 2025
From: SHI, LEI; CHIU, CHIN-TIEN
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 073030/0102 →
PARTIAL RELEASE OF SECURITY INTERESTS Recorded Apr 25, 2025
From: JPMORGAN CHASE BANK, N.A., AS AGENT
To: SANDISK TECHNOLOGIES, INC.
Reel/Frame 071382/0001 →
SECURITY AGREEMENT Recorded Apr 25, 2025
From: SANDISK TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
Reel/Frame 071050/0001 →
PATENT COLLATERAL AGREEMENT Recorded Aug 23, 2024
From: SANDISK TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A., AS THE AGENT
Reel/Frame 068762/0494 →
CHANGE OF NAME Recorded Jun 27, 2024
From: SANDISK TECHNOLOGIES, INC.
To: SANDISK TECHNOLOGIES, INC.
Reel/Frame 067982/0032 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 29, 2024
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: SANDISK TECHNOLOGIES, INC.
Reel/Frame 067567/0682 →
PATENT COLLATERAL AGREEMENT - DDTL LOAN AGREEMENT Recorded Aug 21, 2023
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A.
Reel/Frame 067045/0156 →
PATENT COLLATERAL AGREEMENT - A&R LOAN AGREEMENT Recorded Aug 21, 2023
From: WESTERN DIGITAL TECHNOLOGIES, INC.
To: JPMORGAN CHASE BANK, N.A.
Reel/Frame 064715/0001 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 16, 2022
From: SHI, SARA; ZHANG, CONG; CHIU, HOPE
To: WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 060820/0619 →
Continuity (1)
Related Publication 20240063092A1 · Feb 22, 2024
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