Imaging Device Glass Lid Bonding Step Portion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Solid-state imaging devices face issues with the glass lid peeling off during reflow heating due to weak bonding, leading to size increase and increased material costs, and the use of beads-containing adhesive layers complicates production and introduces thermal expansion issues.
Innovation Solution
A manufacturing method involving a container with a step portion on its side wall and a cover frame bonded with adhesive layers to secure the glass lid, providing a wide bonding area without increasing the container's size, using ultraviolet-setting and thermosetting adhesives for high positional accuracy and bonding strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the bonding area between the glass lid and container is increased to prevent peeling during reflow heating, then the bonding strength is improved, but the container size increases and material costs increase
Solution Approach 1:
The patent applies this principle by forming a step portion on the side wall of the container, creating a multi-level bonding structure. The first adhesive layer bonds the glass lid to the top surface of the side wall, while the second adhesive layer bonds to the side surface of the step portion. This vertical dimensionality increase provides additional bonding area without expanding the horizontal container footprint, thus improving bonding strength while maintaining compact size.
2Strength
If beads-containing adhesive layers are used to enhance bonding, then the bonding strength is improved, but the production process becomes more complicated and thermal expansion issues arise
Solution Approach 1:
The patent extracts and eliminates the beads component from the adhesive layer. Instead of using beads-containing adhesive that complicates production and causes thermal expansion mismatches, the invention achieves enhanced bonding strength through the step portion structure combined with standard adhesive materials. This simplifies the production process and avoids thermal expansion issues while maintaining bonding performance.
3Ease of manufacture
If a simple flat bonding structure is used, then the manufacturing process is simple, but the bonding strength is insufficient to prevent glass lid peeling during reflow heating
Solution Approach 1:
The patent segments the bonding interface into distinct regions: a first adhesive layer bonding the glass lid to the top surface of the side wall, and a second adhesive layer bonding to the side surface of the step portion. This segmentation creates multiple bonding zones that work together to prevent glass lid peeling during reflow heating, while the step portion itself is formed through straightforward manufacturing processes that maintain manufacturing simplicity.
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
This method ensures strong bonding of the glass lid without increasing the container's size, reducing material costs, and preventing peeling during reflow heating, while maintaining production efficiency and minimizing thermal stress.
Implementation Method 1
a glass lid which is bonded to the top surface of the side wall with a first adhesive layer
Implementation Method 2
a cover frame which is disposed on the step portion and bonded to the side surface of the step portion and an outer circumferential surface of the glass lid with a second adhesive layer
Data Source
AI summary
An imaging device includes: a container including a bottom plate and a side wall provided on an outer circumferential portion of the bottom plate; a step portion which is formed in a top outer circumferential portion of the side wall and includes: a horizontal surface that is located at a lower position than a top surface of the side wall; and a side surface that connects the top surface of the side wall to the horizontal surface; an imaging element mounted on the bottom plate; a glass lid which is bonded to the top surface of the side wall with a first adhesive layer; and a cover frame which is disposed on the step portion and bonded to the side surface of the step portion and an outer circumferential surface of the glass lid with a second adhesive layer.