Thin Die Release Using Sacrificial Layer Dissolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Thinned semiconductor dies experience micro-cracks and reduced yield during the dicing process due to uneven forces when ejected from adhesive layers, particularly when the substrate thickness is 50 μm or less, leading to reliability issues and increased throughput time.
Innovation Solution
A fluid-based method is employed to dissolve a sacrificial layer between the semiconductor die and the mount tape, using a perforated mount tape and an ejection component to inject and collect the fluid, thereby releasing the die without mechanical forces, which includes a support component to maintain stability during the process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If thinned semiconductor dies are ejected from adhesive layer using mechanical forces, then the dicing process can be completed, but micro-cracks occur in dies with thickness of 50 μm or less, reducing yield and reliability
Solution Approach 1:
The patent replaces the mechanical ejection system with a chemical dissolution system. Instead of using mechanical forces to eject the semiconductor die from the adhesive layer, the invention uses a fluid to dissolve the sacrificial layer, allowing the die to be released without mechanical stress. This substitution eliminates the harmful mechanical forces that cause micro-cracks in thinned dies while maintaining the ability to complete the dicing process.
Solution Approach 2:
The patent introduces a sacrificial layer as an intermediary between the semiconductor die and the adhesive layer. This sacrificial layer is designed to be selectively dissolved by a fluid, serving as a temporary mediator that holds the die during processing and then releases it without mechanical force. The sacrificial layer acts as a buffer that protects the thin die from direct mechanical contact and stress during the release process.
2Length of stationary object
If substrate thickness is reduced to 50 μm or less, then overall package thickness is reduced, but the risk of generating micro-cracks during ejection increases significantly
Solution Approach 1:
The patent replaces mechanical ejection with chemical dissolution to enable safe handling of ultra-thin substrates (50 μm or less). By using fluid-based dissolution of the sacrificial layer instead of mechanical forces, the system can process extremely thin substrates without inducing the uneven forces that would cause micro-cracks, thus enabling thickness reduction while maintaining reliability.
Solution Approach 2:
The sacrificial layer serves as a pre-established protective cushion between the thin substrate and the adhesive layer. This layer is designed to provide mechanical support during handling and processing, then be selectively removed through chemical dissolution. The cushioning effect protects the ultra-thin substrate from stress and deformation throughout the process, enabling safe reduction to 50 μm or less thickness.
3Loss of time
If dicing process is accelerated for thinned substrates, then throughput time decreases, but the likelihood of micro-crack generation increases
Solution Approach 1:
The patent replaces mechanical ejection with fluid-based dissolution, which enables faster processing without compromising die integrity. The chemical dissolution process can be performed more quickly and uniformly than mechanical ejection, reducing throughput time while eliminating the micro-crack generation problem that plagues accelerated mechanical processes for thinned substrates.
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 method improves yield and reliability by reducing the risk of die cracks and decreases throughput time, allowing for thinner semiconductor packages.
Implementation Method 1
A fluid-based method is employed to dissolve a sacrificial layer between the semiconductor die and the mount tape
Data Source
AI summary
Methods for releasing thinned semiconductor dies from a mount tape and associated apparatuses are disclosed. In one embodiment, a sacrificial layer may be disposed at a back side of thinned substrate including semiconductor dies. The sacrificial layer includes materials soluble in contact with a fluid (and/or vapor). A sheet of perforated mount tape may be attached to the sacrificial layer and an ejection component may be provided under a target semiconductor die to be released. The ejection component is configured to create a locally confined puddle of the fluid under the target semiconductor die such that the sacrificial layer is removed to release the target semiconductor die from the mount tape. Further, a support component may be provided to pick up the target semiconductor die after the target semiconductor die is released from the mount tape.