Adhesive Dispense Unit With Reciprocating Pin for Leadframe Warpage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The warping of leadframes in semiconductor devices causes positional inaccuracy during adhesive dispensing, leading to inconsistent adhesive application and reduced throughput in die bonding machines, as the time of contact between the adhesive droplet and the leadframe varies with the degree of warping, affecting the accuracy and repeatability of the dispensing process.
Innovation Solution
An adhesive dispense unit featuring a pin member with a downstand portion that is reciprocably biased within a sheath portion, ensuring the leadframe is flattened against the work holder, allowing consistent adhesive dispensing by controlling the distance between the dispense nozzle and the leadframe, thereby maintaining precise adhesive volume control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a fixed downstand member is used to flatten the leadframe, then the leadframe positioning is improved, but the adhesive droplet contact time becomes inconsistent due to varying warping degrees
Solution Approach 1:
The pin member is made reciprocating between the dispense nozzle and the leadframe surface, transitioning from a static fixed downstand to a dynamic adjustable position. This allows the pin to adapt to varying leadframe warping degrees while maintaining consistent adhesive droplet formation and contact timing, resolving the contradiction between positioning accuracy and dispensing repeatability.
Solution Approach 2:
The reciprocating pin member provides real-time feedback on the leadframe surface position, allowing the system to adjust the pin's extension distance accordingly. This feedback mechanism ensures that the adhesive droplet is released at the optimal moment regardless of warping variations, maintaining both positioning accuracy and dispensing consistency.
2Object-generated harmful factors
If the spacing between dispense head and leadframe is reduced to control droplet size, then adhesive contamination is reduced, but positioning accuracy becomes more sensitive to leadframe warping
Solution Approach 1:
The reciprocating pin member acts as an intermediary between the dispense nozzle and the leadframe surface. It maintains a controlled, minimal spacing that prevents adhesive contamination while compensating for leadframe warping through its reciprocating motion, thereby protecting against contamination without sacrificing positioning accuracy.
3Adaptability or versatility
If the leadframe warping is allowed to vary, then manufacturing flexibility is maintained, but adhesive dispensing accuracy deteriorates
Solution Approach 1:
The reciprocating pin member dynamically adapts to different leadframe warping degrees by adjusting its extension distance, allowing the system to maintain dispensing accuracy across a range of warping conditions without requiring rigid control of leadframe geometry, thus preserving manufacturing flexibility.
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 solution ensures accurate and repeatable adhesive dispensing, reduces the size of packages, increases throughput, and minimizes downtime for cleaning, as the pin member's reciprocating action maintains consistent contact with the leadframe, even with varying degrees of warping up to 10 mm, enhancing the overall efficiency of the die bonding process.
Implementation Method 1
The down stand portion may be biased within the sheath portion by a resilient bias member.
Implementation Method 2
The adhesive droplet at the opening of the adhesive dispense head 106 may be formed by capilliary action
Data Source
AI summary
This disclosure relates to an adhesive dispense unit for a semiconductor die bonding apparatus. The adhesive dispense unit includes an adhesive dispense nozzle and a pin member; the pin member comprising a down stand portion and a sheath portion, and the down stand is reciprocateable within the sheath portion.