Dome Collet Pressure Profile for Multi-Chip Die Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In manufacturing multi-chip semiconductor packages, adhesive films used for attaching memory chips to controller and spacer chips face issues such as shrinkage and peeling due to height differences, leading to insufficient molding material filling and adhesive bleeding.
Innovation Solution
A die attaching apparatus with a collet body and adsorption member featuring a convex dome-shaped first adsorption surface and peripheral flat adsorption surface, along with vacuum passageways, is used to apply controlled pressure for improved bonding, matching the height difference between chips and reducing stress on the adhesive.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pressure for pressing the memory chip is increased to prevent adhesive film peeling, then bonding quality improves, but adhesive film bleeding occurs causing insufficient molding material filling
Solution Approach 1:
The adsorption member is designed with a first adsorption portion having a convex dome shape that corresponds to the height difference between the controller chip and spacer chip. This creates localized varying pressure distribution - higher pressure at the center where the height difference exists and lower pressure at the periphery - allowing the adhesive film to bond properly without bleeding while ensuring complete molding material filling.
2Strength
If adhesive film is used to attach memory chip, then bonding is achieved, but adhesive film shrinks during curing process causing peeling at interface
Solution Approach 1:
The convex dome-shaped first adsorption portion is designed in advance to match the height difference between chips. This pre-configured geometry compensates for the adhesive film shrinkage that occurs during curing, maintaining uniform contact pressure across the bonding interface and preventing peeling without requiring excessive pressing force.
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 apparatus enhances adhesive film bonding quality by maintaining pressure and reducing stress, preventing adhesive bleeding and ensuring complete molding material filling during the manufacturing process.
Implementation Method 1
A die attaching apparatus includes a collet body having a first vacuum passageway, and an adsorption member coupled with a bottom surface of the collet body
Implementation Method 2
the convex dome shaped first adsorption surface may generate pressure for good bonding between an adhesive film and the controller chip
Data Source
AI summary
A die attaching apparatus includes a collet body with a first vacuum passageway formed therein, and an adsorption member coupled with a bottom surface of the collet body. The adsorption member includes a first adsorption portion in the first region and having a first adsorption surface with a convex dome shape, and a second adsorption portion in a second region that extends peripherally around the first region and having a second adsorption surface. The second adsorption portion includes a plurality of second vacuum passageways formed therein that are in fluid communication with the first vacuum passageway.