Hybrid Bond Pad Layout for Die Alignment Under Warpage

Solution Overview

Problem

As semiconductor devices undergo miniaturization, processes such as die thinning and bonding face challenges due to warpage and expansion, leading to misalignment and reduced contact area between metal pads, which affects the bonding and electrical coupling efficiency.

Innovation Solution

Increasing the width and adjusting the location of metal pads on the first semiconductor device to account for expansion, ensuring better alignment and contact with corresponding pads on the second semiconductor device, and using hybrid bonding techniques to enhance the bonding process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If die thinning and bonding processes are performed with standard metal pad dimensions, then manufacturing complexity is reduced, but misalignment and reduced contact area occur due to warpage and expansion

Engineering Contradiction:

Improvealignment precisionVSAvoidpad design complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The metal pads are designed with pre-calculated increased dimensions before the bonding process to compensate for the expected warpage and expansion that will occur during die thinning and bonding. This preliminary adjustment ensures that after deformation, the pads still align correctly and maintain adequate contact area, resolving the misalignment issue without adding complex real-time adjustment mechanisms.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The dimensions of the metal pads are deliberately changed (increased) from the standard design parameters. By modifying the pad width and contact area parameters in advance, the design accommodates the dimensional changes caused by warpage and expansion during processing, thereby maintaining alignment precision without increasing manufacturing complexity.

Inventive Principle:

Principle #35Parameter changes

2Area of stationary object

If metal pad width is increased to compensate for expansion, then contact area is improved, but manufacturing precision requirements increase

Engineering Contradiction:

Improvecontact areaVSAvoidalignment precision

Core Design Contradiction:

Area of stationary objectVSManufacturing precision

Solution Approach 1:

The metal pads are designed with pre-calculated increased dimensions before the bonding process to compensate for the expected warpage and expansion that will occur during die thinning and bonding. This preliminary adjustment ensures that after deformation, the pads still align correctly and maintain adequate contact area, resolving the misalignment issue without adding complex real-time adjustment mechanisms.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The dimensions of the metal pads are deliberately changed (increased) from the standard design parameters. By modifying the pad width and contact area parameters in advance, the design accommodates the dimensional changes caused by warpage and expansion during processing, thereby maintaining alignment precision without increasing manufacturing complexity.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS11916031B2Semiconductor device and method of manufacturing

Publication Date: 2024.02.27 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

A semiconductor device including a first die and a second die bonded to one another. The first die includes a first passivation layer over a substrate, and first bond pads in the first passivation layer. The second die includes a second passivation layer, which may be bonded to the first passivation layer, and second bond pads in the second passivation layer, which may be bonded to the first bond pads. The second bond pads include inner bond pads and outer bond pads. The outer bond pads may have a greater diameter than the inner bond pads as well as the first bond pads.