Cavity Package Encapsulation Layout for Bonding and Cleanliness

Solution Overview

Problem

Existing package structures with cavities face poor bonding force and reliability due to the use of encapsulants with poor fluidity and high viscosity, which contaminates the cavity and affects product performance.

Innovation Solution

A package structure with a cavity is designed, featuring a first encapsulation layer with higher fluidity than the second encapsulation layer, positioned on the edge of the cavity and substrate, and the second encapsulation layer on the surface of the first encapsulation layer, ensuring the cavity is retained and enhancing bonding force and product reliability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an encapsulant with poor fluidity and high viscosity is used to avoid contaminating the cavity, then the cavity remains clean, but the bonding force between the encapsulant and substrate deteriorates

Engineering Contradiction:

Improvecavity cleanlinessVSAvoidbonding force

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The encapsulation layer is divided into two distinct layers: a first encapsulation layer with higher fluidity for strong bonding to the substrate, and a second encapsulation layer with lower fluidity to protect the cavity. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the encapsulation structure are assigned different material properties. The first encapsulation layer (outer layer) has high fluidity and low viscosity for optimal substrate bonding, while the second encapsulation layer (inner layer) has low fluidity and high viscosity to prevent cavity contamination. Each layer's local properties are optimized for its specific functional requirement.

Inventive Principle:

Principle #3Local quality

2Strength

If an encapsulant with good fluidity and low viscosity is used to improve bonding force, then the bonding force between encapsulant and substrate improves, but the cavity becomes contaminated

Engineering Contradiction:

Improvebonding forceVSAvoidcavity cleanliness

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The encapsulation layer is divided into two distinct layers: a first encapsulation layer with higher fluidity for strong bonding to the substrate, and a second encapsulation layer with lower fluidity to protect the cavity. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the encapsulation structure are assigned different material properties. The first encapsulation layer (outer layer) has high fluidity and low viscosity for optimal substrate bonding, while the second encapsulation layer (inner layer) has low fluidity and high viscosity to prevent cavity contamination. Each layer's local properties are optimized for its specific functional requirement.

Inventive Principle:

Principle #3Local quality

3Device complexity

If a single encapsulation layer is used, then the structure is simple, but it cannot simultaneously achieve strong bonding and cavity protection

Engineering Contradiction:

Improveencapsulation structureVSAvoidproduct reliability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The encapsulation layer is divided into two distinct layers: a first encapsulation layer with higher fluidity for strong bonding to the substrate, and a second encapsulation layer with lower fluidity to protect the cavity. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The encapsulation structure uses a composite of two different encapsulation materials with distinct properties. The first material provides bonding functionality, while the second material provides cavity protection. This composite approach enables the system to achieve multiple functions that a single material cannot provide.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS20250006578A1Package structure with cavity and related packaging method

Publication Date: 2025.01.02 JCET GROUP CO LTD

AI summary

The present disclosure relates to the field of packaging technology, and discloses a package structure with a cavity and a related packaging method. A first encapsulation body arranged on a surface of a substrate is covered by using an encapsulation layer including a first encapsulation layer and a second encapsulation layer, and a cavity is formed between the first encapsulation body and the substrate; and a material corresponding to the first encapsulation layer has a fluidity greater than that of a material corresponding to the second encapsulation layer, so that the first encapsulation layer is positioned on an edge of an inner part of the cavity and the surface of the substrate of an outer part of the cavity, and the second encapsulation layer is positioned on the surface of the first encapsulation layer of an outer part of the cavity.