Deformable IC Package Lid for Hermetic Moisture Sealing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional IC package lids allow moisture penetration due to gaps between the lid and the substrate, which degrades the reliability of the package by allowing outside moisture in and affecting air pressure.

Innovation Solution

A lid with a deformable plastic film in the central area and a metallic periphery area attached to the substrate, where the film is downward arc-shaped and made of materials like Tin, providing a hermetic seal by eliminating gaps between the lid and the substrate.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stress or pressure

If gaps are left between the lid and substrate, then air pressure can be relieved during assembly, but moisture can penetrate into the package

Engineering Contradiction:

Improveair pressureVSAvoidmoisture protection

Core Design Contradiction:

Stress or pressureVSReliability

Solution Approach 1:

The patent employs a deformable lid with a thin film structure that can flex and deform during the solder reflow process. This flexible lid allows internal air pressure to be relieved during assembly while simultaneously providing a continuous sealing surface that prevents moisture penetration, resolving the contradiction between pressure relief and moisture protection

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The lid's physical parameters (shape, thickness, material properties) are specifically designed to change under thermal stress during soldering. The lid transitions from a rigid structure to a deformable state during reflow, allowing pressure equalization, then returns to its original sealed configuration after cooling, preventing moisture ingress

Inventive Principle:

Principle #35Parameter changes

2Reliability

If a continuous bonding layer is used to seal the package, then moisture protection is improved, but air pressure cannot be relieved during assembly

Engineering Contradiction:

Improvemoisture protectionVSAvoidair pressure

Core Design Contradiction:

ReliabilityVSStress or pressure

Solution Approach 1:

The lid is designed with dynamic characteristics, allowing it to deform during the soldering process when thermal expansion occurs. This dynamic behavior enables the lid to temporarily accommodate pressure changes during assembly while maintaining a continuous seal, unlike static rigid lids that would either leak or build excessive pressure

Inventive Principle:

Principle #15Dynamics

3Ease of manufacture

If gaps are left between lid and substrate, then assembly is easier, but the hermetic seal is compromised

Engineering Contradiction:

Improveassembly easeVSAvoidhermetic seal

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The thin film lid structure is inherently more compliant and easier to attach to the substrate during assembly. The flexibility of the film allows for easier alignment and bonding while still forming a continuous hermetic seal, improving both manufacturability and sealing performance compared to rigid lids

Inventive Principle:

Principle #30Flexible shells and thin films

Data Source

PatentUS20250105071A1Packaged Integrated Circuit Device Having A Deformable Lid, And Associated Methods

Publication Date: 2025.03.27 NXP USA INC

AI summary

An packaged integrated circuit device comprises a substrate having a top surface and a bottom surface; a die mounted on the top surface of the substrate; a lid comprising a central area and a peripheral area; wherein the central area comprises an deformable film above the die and the peripheral area is attached to the top surface of the substrate, and wherein the deformable film in the central area is concave towards the substrate. Corresponding manufacturing methods are also disclosed.