Concave Semiconductor Chip Warp for Void-Free Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices face reliability issues due to voids in the bonding material between the semiconductor chip and the insulation substrate, which deteriorate heat dissipation and long-term performance, as reducing chip warp does not effectively eliminate these voids.
Innovation Solution
A semiconductor device with a semiconductor chip warped into a concave shape, mounted on an insulation substrate with a heat-dissipating base plate and sealed by a resin section, featuring bumps in the joint to stabilize the bonding material thickness and release voids externally.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the semiconductor chip is made thinner to improve electrical characteristics, then cost and energy loss are reduced, but the chip warps into a convex shape causing voids in the bonding material
Solution Approach 1:
Instead of attempting to flatten the convex-warped chip, the invention inverts the approach by intentionally allowing the chip to warp convexly but designing the bonding structure to accommodate this warp. The bonding material is applied in a manner that fills the convex warp, and the bonding process is optimized to bond the chip in its warped state, thereby eliminating voids while maintaining the thin chip design.
Solution Approach 2:
The invention changes the parameters of the bonding material and bonding process to accommodate the chip warp. Specifically, the bonding material's viscosity, bonding temperature, and bonding pressure are optimized to ensure proper filling of the convex warp and complete bonding without voids, thereby resolving the contradiction between thin chip design and warp-induced voids.
2Reliability
If the chip warp amount is reduced to minimize voids, then bonding quality improves, but the convex warp cannot be fully eliminated and voids still remain in the bonding material
Solution Approach 1:
The invention converts the harmful convex warp into a beneficial feature by designing the bonding process to utilize the warp. The convex warp is intentionally preserved, and the bonding material is applied to fill this warp, creating a mechanically advantageous bonding structure that actually improves bonding quality and eliminates voids when properly processed.
Solution Approach 2:
The invention applies preliminary action by pre-shaping the bonding material or pre-positioning it to accommodate the expected convex warp of the chip before bonding. This preliminary preparation ensures that when bonding occurs, the material is already positioned to fill the warp completely, preventing void formation and improving bonding quality.
3Temperature
If voids are reduced in the bonding material, then heat dissipation performance improves, but long-term reliability is still deteriorated by remaining voids
Solution Approach 1:
The invention ensures continuity of useful action by creating a continuous, void-free bonding interface that maintains consistent thermal conduction throughout the device's operational life. The bonding process is optimized to completely eliminate voids, ensuring uninterrupted heat flow from the chip through the bonding material to the substrate, thereby maintaining both heat dissipation performance and long-term reliability.
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
This configuration reduces voids in the bonding material, enhancing the semiconductor device's reliability and heat dissipation properties by ensuring uniform bonding material thickness and preventing thermal resistance increases.
Implementation Method 1
a semiconductor chip warped into a concave shape... A warp amount of the semiconductor chip warped into a concave shape is equal to or greater than 1 μm and less than a height of the bump... voids remaining in the bonding material are easily released to the outside of the bonding material
Data Source
AI summary
An object of the present invention is to provide a highly reliable semiconductor device that allows voids remaining in a bonding material to be reduced. The semiconductor device includes a semiconductor chip, an insulation substrate, a metal base plate, a resin section, and a bump. The semiconductor chip is warped into a concave shape. On the insulation substrate, the semiconductor chip is mounted by bonding. The metal base plate has the insulation substrate mounted thereon and has a heat dissipation property. The resin section seals the insulation substrate and the semiconductor chip. The bump is disposed in a joint between the semiconductor chip and the insulation substrate. A warp amount of the semiconductor chip warped into a concave shape is equal to or greater than 1 μm and less than a height of the bump.