Semiconductor Package Molding Cavities for Void-Free Multi-Chip Filling
Solution Overview
Problem
The challenge in semiconductor packaging is the occurrence of defects such as non-filling and void traps during the molding process when multiple semiconductor chips are mounted in a single package, due to reduced upper and side margins of the molding member, leading to incomplete coverage and structural weaknesses.
Innovation Solution
A molding apparatus with an upper mold and a bottom mold, featuring adjustable side cavities and a wedge mechanism-driven positioning system, ensures precise alignment and spacing to accommodate multiple semiconductor chips, preventing void traps and ensuring complete coverage with a molding material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If multiple semiconductor chips are mounted in one package, then package capacity and functionality are improved, but upper and side margins of the molding member are reduced causing non-filling and void trap defects
Solution Approach 1:
The molding member is divided into multiple segments: a main body portion and multiple protrusion portions that extend toward the semiconductor chips. This segmentation allows the molding material to flow through dedicated channels (protrusions) rather than attempting to fill narrow gaps directly, preventing non-filling defects while accommodating multiple chips in the package
Solution Approach 2:
The protrusion portions act as intermediary structures between the main body of the molding member and the semiconductor chips. These protrusions create controlled flow paths for the molding material, mediating the filling process to ensure complete coverage without causing void traps or non-filling defects
2Quantity of substance
If multiple semiconductor chips are mounted in one package, then package capacity is improved, but molding material flow becomes incomplete leading to non-filling defects
Solution Approach 1:
The molding member is divided into multiple segments: a main body portion and multiple protrusion portions that extend toward the semiconductor chips. This segmentation allows the molding material to flow through dedicated channels (protrusions) rather than attempting to fill narrow gaps directly, preventing non-filling defects while accommodating multiple chips in the package
Solution Approach 2:
The protrusion portions are pre-positioned to extend toward the semiconductor chips before the molding material is supplied. This preliminary configuration creates ready-made flow paths that guide the molding material to completely fill the space around all chips, ensuring complete coverage and preventing non-filling defects
3Quantity of substance
If multiple semiconductor chips are mounted in one package, then package capacity is improved, but void trap defects occur due to restricted molding material flow
Solution Approach 1:
The molding member is divided into multiple segments: a main body portion and multiple protrusion portions that extend toward the semiconductor chips. This segmentation allows the molding material to flow through dedicated channels (protrusions) rather than attempting to fill narrow gaps directly, preventing non-filling defects while accommodating multiple chips in the package
Solution Approach 2:
The geometry of the molding member is changed by adding protrusion portions that modify the flow parameters of the molding material. These protrusions create controlled flow paths that maintain adequate flow velocity and pressure distribution, preventing the formation of void traps while accommodating multiple semiconductor chips
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 enhances the reliability of semiconductor packages by preventing defects like non-filling and void traps, ensuring proper molding material flow and complete coverage of semiconductor chips, thereby improving the structural integrity and functionality of the packages.
Implementation Method 1
the first driving part and the second driving part are operated by a wedge mechanism
Data Source
AI summary
A molding apparatus for fabricating a semiconductor package includes an upper mold including an upper cavity, a first side cavity at a first side of the upper cavity, a second side cavity formed at an opposite second side of the upper cavity, and a first driving part connected to the first side cavity and configured to move the first side cavity in a first direction, and a bottom mold including a bottom cavity configured to receive a molding target including a package substrate and at least one semiconductor chip. A width in the first direction between the first side cavity and the second side cavity may be smaller than a width of the package substrate in the first direction and greater than a width in the first direction between a first boundary and a second boundary of the at least one semiconductor chip.