Semiconductor Package Apertures for Void Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing semiconductor packaging processes often result in voids and defects due to trapped flux residues during the molding process, which affect the reliability and yield of semiconductor packages.
Innovation Solution
Incorporating apertures or slots between substrates to facilitate the outflow of materials from cavities, aligned with removable regions, which are subsequently removed during the singulation process to minimize defects and voids in the encapsulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional molding process is used without apertures, then complete encapsulation is achieved, but voids and defects form due to trapped flux residues
Solution Approach 1:
The substrate is segmented by forming apertures or slots that divide the encapsulation cavity into regions with controlled material flow paths. This segmentation allows flux residues to escape through designated channels while maintaining encapsulation integrity, resolving the contradiction between complete encapsulation and void prevention
Solution Approach 2:
The aperture acts as an intermediary element between the encapsulation cavity and the external environment. It provides a controlled pathway for flux residues to escape during molding while preventing premature exposure of sensitive components, enabling both complete encapsulation and defect mitigation
2Manufacturing precision
If apertures are formed in substrates, then outflow of materials is facilitated reducing voids, but additional manufacturing steps are required
Solution Approach 1:
The aperture formation step is merged with the substrate preparation process by using the same routing and drilling infrastructure already present in PCB manufacturing. This integration minimizes additional process complexity while achieving the benefit of improved encapsulation quality
Solution Approach 2:
The aperture structure serves multiple functions: it facilitates material outflow during molding, provides alignment references for stacking, and can be used for subsequent wire bonding or testing. This multi-functionality justifies the added manufacturing step by delivering multiple benefits from a single feature
3Manufacturing precision
If apertures and removable regions are removed during singulation, then defect-free packages are produced, but simultaneous precise removal is required
Solution Approach 1:
The aperture and removable region are designed with pre-defined geometries and locations that align with standard singulation patterns. This preliminary configuration allows the singulation process to remove these features automatically along with the substrate, eliminating the need for separate removal steps while maintaining precision
Data Source
AI summary
Semiconductor packages with multiple substrates can incorporate apertures or slots between devices to minimize or reduce formation of defects during a molding process. The apertures or slots can be formed adjacent a top substrate in alignment with removable regions adjacent a bottom substrate whereby the apertures or slots can facilitate outflow of materials from cavities between the substrates. The apertures or slots may subsequently be removed in conjunction with the removable regions during a singulation process thereby producing the desired semiconductor packages with improved device reliability and yield.