Semiconductor Package Substrate Grinding for Heat Sink Bonding

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional semiconductor devices face challenges in enhancing the adhesion and flatness of the reverse-side metal layer on the support substrate to improve bonding with heat sinks, which is crucial for effective heat dissipation and structural integrity.

Innovation Solution

The semiconductor device incorporates a support substrate with a grinding trace on the bottom surface of the first metal layer to enhance flatness, ensuring improved adhesion and bonding with a heat sink, while utilizing a conductive substrate and conductive members to form a path for main circuit current.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the bottom surface of the reverse-side metal layer is used for heat sink bonding without additional processing, then the manufacturing process is simple, but the adhesion and flatness are insufficient

Engineering Contradiction:

ImproveadhesionVSAvoidprocess complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by performing laser surface treatment on the reverse-side metal layer before heat sink bonding. The laser processing creates a roughened surface with increased surface area and improved微观 structure, which enhances adhesion properties in advance of the bonding process. This preliminary surface preparation ensures reliable bonding while maintaining a relatively simple overall manufacturing process.

Inventive Principle:

Principle #10Preliminary action

2Manufacturing precision

If the bottom surface of the reverse-side metal layer is ground to improve flatness, then the bonding quality improves, but the manufacturing time and cost increase

Engineering Contradiction:

ImproveflatnessVSAvoidmanufacturing time

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent replaces the mechanical grinding process with laser surface treatment. Instead of using mechanical abrasion to achieve flatness and surface preparation, the laser method uses optical energy to selectively remove material and reshape the surface. This substitution maintains high manufacturing precision for flatness while significantly reducing manufacturing time and eliminating the need for complex mechanical grinding equipment.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the physical state and properties of the metal layer surface through laser processing. By controlling laser parameters such as power, scanning speed, and pulse duration, the surface undergoes phase changes and reorganization that result in improved flatness and enhanced bonding characteristics. This parameter-based approach allows precise control over surface quality without the time-consuming mechanical processes.

Inventive Principle:

Principle #35Parameter changes

3Strength

If conventional bonding methods are used without surface treatment, then the manufacturing process is simple, but the bonding strength and heat dissipation efficiency are insufficient

Engineering Contradiction:

Improvebonding strengthVSAvoidease of manufacture

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The patent changes the surface parameters of the metal layer through laser treatment, creating a roughened topology and modified微观 structure that dramatically improves bonding strength. The laser processing alters surface area, roughness, and thermal properties, enabling strong bonding without complex mechanical preparation methods. This maintains relative manufacturing simplicity while achieving superior bonding performance.

Inventive Principle:

Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution achieves enhanced heat dissipation and structural integrity by improving the bonding between the support substrate and heat sink, thereby optimizing the performance and reliability of the semiconductor device.

Implementation Method 1

a first resin reverse surface is formed by irradiating at least a region of the sealing resin that surrounds the bottom surface with a laser from the second side in the thickness direction

Methodology Applied

Scientific EffectLaser ablation: Laser Ablation

Implementation Method 2

the bottom surface includes a grinding trace

Methodology Applied

Scientific EffectAbrasion: Abrasion

Data Source

PatentUS20250364341A1Semiconductor device, semiconductor device assembly, vehicle, and method for manufacturing semiconductor device

Publication Date: 2025.11.27 ROHM CO LTD

AI summary

A semiconductor device includes a support substrate, a semiconductor element, and a sealing resin. The support substrate includes a support surface facing a first side in the thickness direction and a bottom surface facing a second side in the thickness direction. The semiconductor element is disposed on the support surface. The sealing resin covers the semiconductor element and a portion of the support substrate. The bottom surface is exposed from the sealing resin and includes a grinding trace. The sealing resin includes a resin obverse surface facing the first side in the thickness direction and a first resin reverse surface facing the second side in the thickness direction. The first resin reverse surface surrounds the bottom surface as viewed in the thickness direction and is located on the first side in the thickness direction relative to the bottom surface.