Fingerprint Sensor Package with Composite Substrate and Molded Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fingerprint sensor packages face challenges in maintaining reliability and sensitivity while being compact and resistant to repeated use, as existing designs often suffer from mechanical stress and noise interference, which affects their performance and durability.
Innovation Solution
A fingerprint sensor package design featuring a first substrate with a core insulating layer and a second substrate with sensing patterns, bonded together with thermocompression bonding, and a molded layer covering the controller chip, which enhances mechanical stability and reduces noise interference, ensuring reliable fingerprint recognition even after repeated use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the fingerprint sensor package is made smaller and thinner, then the size and height are reduced, but the mechanical strength and reliability deteriorate
Solution Approach 1:
The patent employs a multi-layer composite structure consisting of a first substrate, second substrate, core insulating layer, and molded layer. Each layer is made of different materials optimized for specific functions: the substrates provide mechanical support, the core insulating layer provides electrical insulation, and the molded layer provides protection and filling. This composite approach allows the package to maintain high mechanical strength while achieving compact dimensions.
Solution Approach 2:
The fingerprint sensor package is divided into multiple functional segments: a first substrate for mounting the controller chip, a second substrate for mounting the sensing patterns, a core insulating layer for electrical insulation, and a molded layer for protection. This segmentation allows each component to be optimized independently for its specific function while contributing to the overall mechanical strength of the compact package.
2Volume of moving object
If the fingerprint sensor package is made smaller and thinner, then the size and height are reduced, but the reliability under repeated use deteriorates
Solution Approach 1:
The molded layer is specifically designed to fill the through-hole and cover the controller chip, providing beforehand cushioning and protection against mechanical stress and external impacts. This protective structure is built in advance to prevent damage during repeated use, thereby maintaining high reliability in the compact package design.
Solution Approach 2:
The multi-layer composite structure provides distributed mechanical support and stress distribution. The combination of rigid substrates, flexible core insulating layer, and protective molded layer creates a robust structure that maintains reliability under repeated use while keeping the overall package compact.
3Stability of the object's composition
If the through-hole is filled with molded layer, then the mechanical stability is improved, but the external connection pad accessibility is reduced
Solution Approach 1:
The connection pads are segmented into two groups: internal connection pads (first bonding pad and second bonding pad) that are bonded together through the substrate layers to provide mechanical stability, and external connection pads (external connection pad on the edge of the second surface) that are positioned on the outer edge to maintain accessibility. This segmentation allows the molded layer to fill the through-hole for mechanical stability while leaving the external connection pads exposed for electrical connection.
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 design improves the reliability and sensitivity of fingerprint recognition by providing a robust and noise-reduced fingerprint sensor package that maintains performance even after repeated use, with enhanced mechanical stability and reduced noise interference.
Implementation Method 1
a second bonding pad on an edge of the fourth surface and bonded to the first bonding pad
Data Source
AI summary
A fingerprint sensor package includes a first substrate including a core insulating layer including first and second surfaces opposing each other and having a through-hole penetrating through the first surface and the second surface, a first bonding pad along a circumference of the through-hole on the first or second surface, and an external connection pad on an edge of the second surface, a second substrate having a third surface including a sensing region and a peripheral region surrounding the sensing region, and a fourth surface opposing the third surface, the second substrate including a second bonding pad along an edge of the third or fourth surface and bonded to the first bonding pad, and covering the through-hole, a controller chip on the fourth surface, and a molded layer on the second surface of the core insulating layer, covering the controller chip, and spaced apart from the external connection pad.