Semiconductor Package Bonding Structure for Shear Stress Relief

Solution Overview

Problem

Existing semiconductor packaging technologies face challenges in managing shear stress due to thermal expansion and mechanical deformation, leading to potential solder damage and reliability issues.

Innovation Solution

A bonding structure is introduced that includes a support structure with a sub pad and legs connecting to a main pad, designed to attenuate shear stress by using a conductive material like Cu, Ni, Au, Cr, Al, Ag, or Fe, which is formed through a plating process to enhance structural stability and electrical connectivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a direct bonding structure is used between semiconductor chip and package substrate, then manufacturing process is simple, but shear stress from thermal expansion and mechanical deformation causes solder damage and fatigue failure

Engineering Contradiction:

Improvebonding structure manufacturing simplicityVSAvoidsolder joint reliability

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The bonding structure is divided into multiple functional segments: a first bonding part for connecting the semiconductor chip to the package substrate, and a second bonding part for connecting the package substrate to the board. This segmentation allows each part to be optimized independently, with the first bonding part using a simplified direct bonding approach while the second bonding part incorporates stress attenuation features to handle thermal and mechanical stresses from the board-level connections.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The package substrate acts as an intermediary component between the semiconductor chip and the board. By introducing this intermediate layer with appropriate mechanical and thermal properties, the structure mediates the stress transmission between the chip and the board, preventing direct stress transfer that would cause solder damage while maintaining electrical and mechanical connectivity.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If solder is directly bonded between components, then electrical connection is achieved, but shear stress leads to cracks and fatigue failure

Engineering Contradiction:

Improveelectrical connection reliabilityVSAvoidsolder joint strength

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The bonding structure is divided into multiple functional segments: a first bonding part for connecting the semiconductor chip to the package substrate, and a second bonding part for connecting the package substrate to the board. This segmentation allows each part to be optimized independently, with the first bonding part using a simplified direct bonding approach while the second bonding part incorporates stress attenuation features to handle thermal and mechanical stresses from the board-level connections.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The bonding structure incorporates stress attenuation features designed beforehand to cushion against thermal expansion and mechanical deformation stresses. By pre-configuring the bonding structure with appropriate geometry and material properties, the system is prepared to absorb and distribute stresses before they can cause solder damage or fatigue failure during operation.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Stability of the object's composition

If thermal expansion and mechanical deformation are managed rigidly, then structural stability is maintained, but stress concentration causes solder damage

Engineering Contradiction:

Improvestructural stabilityVSAvoidsolder joint reliability

Core Design Contradiction:

Stability of the object's compositionVSReliability

Solution Approach 1:

The bonding structure utilizes changes in geometric parameters and material properties to manage thermal expansion and mechanical deformation. By optimizing the geometry of the bonding interfaces and selecting materials with appropriate thermal and mechanical properties, the structure can accommodate dimensional changes while distributing stresses uniformly, preventing both structural instability and solder joint failure.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12622297B2Bonding structure of semiconductor package device, semiconductor package device, and method for manufacturing the same

Publication Date: 2026.05.05 SAMSUNG ELECTRONICS CO LTD

AI summary

A bonding structure of a semiconductor package device that physically and electrically connects between a semiconductor chip and a package substrate or between a package substrate and a board, the bonding structure includes a solder; a main pad that faces the solder; and an electrically conductive support structure that is connected between the solder and the main pad, the electrically conductive support structure including a sub pad bonded to the solder, the sub pad being spaced apart from the main pad and facing the main pad, and at least one leg extending from the sub pad to the main pad.