Wedge Bonding Tool Notches for Scrubbing Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional wedge bonding systems experience issues such as side scooting of the tip portion, inefficient ultrasonic energy use, and short circuits due to non-desirable scrubbing motions along unintended axes, which affect the quality of wedge bonds and the mechanism used to secure the bonding tool.
Innovation Solution
The introduction of notches or protrusions on the surface of the wedge bonding tool, strategically positioned at anti-nodes to alter the dynamic response and resonant frequencies, reducing unwanted scrubbing motions and improving directional energy delivery and bond quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional wedge bonding tools are used without notches, then the structure is simple and easy to manufacture, but non-desirable scrubbing motions occur along unintended axes causing side scooting and short circuits
Solution Approach 1:
The bonding tool surface is segmented by introducing notches that divide the continuous surface into distinct regions. These notches create discrete contact zones that guide the scrubbing motion along the intended axis while preventing lateral movement, thereby eliminating side scooting and improving bond reliability without significantly complicating the overall tool structure.
Solution Approach 2:
The notches introduce localized structural variations at specific positions on the bonding tool surface. By concentrating geometric features at critical locations (where notches are positioned), the tool achieves directional control of scrubbing motion only where needed, maintaining simplicity in non-critical areas while improving reliability through targeted structural modifications.
2Use of energy by moving object
If conventional wedge bonding tools are used without notches, then the tool structure is simple, but ultrasonic energy is used inefficiently due to parasitic modes
Solution Approach 1:
The notches are strategically positioned to interact with the vibrational modes of the bonding tool during ultrasonic operation. By creating geometric discontinuities at specific locations, the notches modify the tool's vibration characteristics to suppress parasitic modes that cause energy loss, thereby improving ultrasonic energy efficiency while maintaining a relatively simple tool structure.
Solution Approach 2:
The introduction of notches changes the physical parameters of the bonding tool, specifically its mass distribution and stiffness characteristics. These parameter modifications alter the tool's resonant frequencies and mode shapes, enabling better alignment with the ultrasonic drive frequency and reducing energy dissipation through unwanted vibrational modes.
3Ease of operation
If conventional wedge bonding tools are used without notches, then the tool mechanism is simple to secure, but side scooting occurs affecting the securing mechanism
Solution Approach 1:
The notches segment the bonding tool surface to create defined contact regions that constrain lateral movement. This segmentation prevents side scooting that would otherwise cause the tool to shift relative to the securing mechanism (e.g., set screw), maintaining proper alignment and ensuring reliable bonding without compromising the simplicity of the securing mechanism.
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 approach enhances the quality of wedge wire bonding by reducing parasitic modes, improving the alignment of ultrasonic energy delivery, and allowing for a 'drop-in' replacement tool with improved characteristics without altering bonding system parameters, effectively addressing issues of side scooting and energy inefficiency.
Implementation Method 1
strategically positioned at anti-nodes to alter the dynamic response and resonant frequencies, reducing unwanted scrubbing motions
Implementation Method 2
An upper end of a bonding tool is, in many instances, configured to be engaged in a transducer (e.g., an ultrasonic transducer) of an ultrasonic bonding system which causes the bonding tool to vibrate during bonding
Implementation Method 3
Wedge bonding tools (sometimes referred to as 'wedges' and 'bonding wedges'...) are intended to provide a scrubbing motion along on or more axes... This relative motion is provided by a tip portion of the wire bonding tool
Data Source
AI summary
A wedge bonding tool including a body portion including a tip portion is provided. The tip portion includes a working surface configured to contact a wire material during formation of a wedge bond. A plurality of notches are defined by one or more surfaces of the body portion.