Wire Bonding Structure with Pressed Surface for Enhanced Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wire bonding techniques, such as ball bonding, often result in insufficient bonding strength, leading to detachment of the bonding wire from the bonding target, which can cause electrical failures or short-circuits.
Innovation Solution
A wire bonding structure featuring a bond portion with a pressed surface comprising a first and second annular portion connected via a bent portion, where the second annular portion becomes more distant from the bottom surface as it extends outward, enhancing the bonding strength by concentrating pressure effectively during the bonding process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional ball bonding is used to bond wire to bonding target, then the bonding process is simple and fast, but the bonding strength is insufficient leading to wire detachment
Solution Approach 1:
The pressed surface is segmented into multiple functional regions: a first annular portion for initial contact, a second annular portion for enhanced bonding, and a bent portion connecting them. This segmentation allows different regions to contribute differently to the bonding process, improving overall bonding strength while maintaining a manageable structural complexity.
Solution Approach 2:
Different portions of the pressed surface are designed with distinct geometries to perform specific functions. The first annular portion provides a base bonding area, while the second annular portion extends outward to increase contact area and bonding strength locally. This local differentiation of properties enhances bonding reliability without requiring complete structural redesign.
2Reliability
If conventional bonding structure is used, then the process is simple, but the wire may detach causing electrical failures or short-circuits
Solution Approach 1:
The bond portion is divided into functionally distinct segments including the bottom surface for initial bonding, the pressed surface with multiple annular portions for enhanced mechanical interlocking, and side surfaces for structural support. This segmentation ensures that each region contributes to preventing wire detachment and maintaining electrical connection reliability.
Solution Approach 2:
The bent portion connecting the two annular portions introduces a curved geometry that distributes stress more effectively during bonding. This curvature helps prevent stress concentration that could lead to wire detachment, thereby improving electrical connection reliability without excessive geometric complexity.
3Strength
If conventional bonding structure is used, then manufacturing is simple, but bonding strength is insufficient
Solution Approach 1:
The pressed surface is segmented into a first annular portion and a second annular portion connected by a bent portion. The second annular portion extends outward from the first, creating additional contact area with the bonding target. This segmentation increases bonding strength by distributing the bonding force across multiple regions rather than a single flat surface.
Solution Approach 2:
The pressed surface transitions from a simple planar structure to a multi-level annular structure that utilizes vertical and radial dimensions. The second annular portion extends outward in the radial direction and is positioned at different heights, creating a three-dimensional bonding interface that enhances mechanical interlocking and bonding strength.
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 improved bonding structure secures a sufficient bonding strength, reducing the risk of wire detachment and electrical failures, while allowing for a wider range of ultrasonic wave strengths to be used, thus increasing yield and reliability.
Implementation Method 1
enhancing the bonding strength by concentrating pressure effectively during the bonding process
Implementation Method 2
allowing for a wider range of ultrasonic wave strengths to be used
Data Source
AI summary
A wire bonding structure includes a bonding target and a wire with its bond portion bonded to the bonding target. The bond portion has a bottom surface in contact with the bonding target, a pressed surface facing away from the bottom surface in a thickness direction of the bond portion, and a side surface connecting the bottom surface and the pressed surface. The pressed surface includes first and second annular portions connected to each other via a bent portion. The first annular portion is parallel to the bottom surface and positioned on the inner side of the second annular portion as viewed in the thickness direction. The second annular portion becomes more distant from the bottom surface in the thickness direction as extending outward as viewed in the thickness direction, starting from the first bent portion.