POP Semiconductor Package Alignment Marks for Vision Camera Stacking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in the semiconductor industry is accurately aligning package-on-package (POP) type semiconductor packages to prevent misalignment, which can lead to electrical connectivity issues and reduced device performance.
Innovation Solution
The implementation of alignment marks on the lower package substrate, positioned below and near the outer boundaries of the upper package, allows for precise identification and alignment of the upper package using vision cameras, ensuring accurate stacking and electrical connection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If alignment marks are added to the lower package substrate, then manufacturing precision is improved, but device complexity increases
Solution Approach 1:
Alignment marks are pre-formed on the lower package substrate before the upper package is mounted. This preliminary action enables vision cameras to detect and calculate alignment status, achieving precise alignment without adding complexity to the mounting process itself.
Solution Approach 2:
Alignment marks serve as an intermediary element between the lower and upper packages. These marks enable the vision camera to detect alignment status by providing reference points, thereby mediating the alignment process without requiring direct measurement between packages.
2Measurement precision
If vision camera alignment detection is implemented, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent replaces mechanical alignment methods with vision camera-based optical detection. The vision camera captures images of alignment marks and uses image processing to calculate alignment status, substituting mechanical measurement systems with optical-electrical systems that offer higher precision.
Solution Approach 2:
The vision camera creates an optical copy (image) of the alignment marks on the lower package substrate. By analyzing this copied visual information, the system can precisely determine alignment status without physical contact or complex mechanical measurement apparatus.
Data Source
AI summary
Provided are package-on-package (POP)-type semiconductor packages including a lower package having a first size and including a lower package substrate in which a lower semiconductor chip is, an upper redistribution structure on the lower package substrate and the lower semiconductor chip, and alignment marks. The packages may also include an upper package having a second size smaller than the first size and including an upper package substrate and an upper semiconductor chip. The upper package substrate may be mounted on the upper redistribution structure of the lower package and electrically connected to the lower package, and the upper semiconductor chip may be on the upper package substrate. The alignment marks may be used for identifying the upper package, and the alignment marks may be below and near outer boundaries of the upper package on the lower package.