Piezoelectric Actuator Alignment for Die Detachment Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pick-and-place die bonders face challenges in maintaining accurate alignment of the collet and ejector pin due to thermal expansion and complex monitoring requirements, especially when handling smaller semiconductor dice and increasing wafer densities.
Innovation Solution
A die detachment apparatus featuring a positioning device with piezoelectric actuators and flexures that allows the ejector pin to move perpendicular to the pick-up axis, ensuring precise alignment with the pick-and-place tool, utilizing a combination of orthogonal flexural stages and a decoupled Z actuator for independent vertical movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple bond arms are used to increase throughput, then productivity increases, but alignment precision between collet and ejector pin deteriorates due to thermal expansion and positioning complexity
Solution Approach 1:
The ejector pin positioning system transitions from a static fixed-position design to a dynamic adjustable design. The piezoelectric actuators enable the ejector pin to dynamically adjust its position perpendicular to the pick-up axis in real-time, compensating for thermal expansion and maintaining alignment precision even as multiple bond arms operate simultaneously and generate heat.
Solution Approach 2:
The system changes the positional parameters of the ejector pin by controlling the piezoelectric actuators. These actuators convert electrical signals to precise mechanical displacements, allowing the ejector pin to adjust its X and Y coordinates independently to maintain alignment with the collet despite thermal drift or positioning variations.
2Device complexity
If fixed radial distance positioning is used for bond arms, then device complexity is reduced, but alignment reliability deteriorates due to thermal expansion effects
Solution Approach 1:
The positioning system performs self-alignment through the piezoelectric actuators that automatically adjust the ejector pin position based on real-time requirements. The system monitors and corrects its own alignment without external intervention, compensating for thermal expansion and maintaining reliable alignment between the collet and ejector pin throughout the bonding process.
Solution Approach 2:
The system incorporates alignment feedback mechanisms that detect positional deviations of the ejector pin relative to the collet. This feedback information is used to control the piezoelectric actuators, which then adjust the ejector pin position to eliminate the detected deviation, ensuring continuous reliable alignment despite thermal effects.
3Manufacturing precision
If manual monitoring and adjustment of alignment is performed, then manufacturing precision can be maintained, but loss of time increases due to close monitoring requirements
Solution Approach 1:
The manual mechanical adjustment process is replaced with an automated electromechanical system using piezoelectric actuators. These actuators receive electrical control signals and automatically adjust the ejector pin position with high precision, eliminating the need for manual monitoring and physical adjustment, thereby maintaining alignment precision while significantly reducing the time required.
Solution Approach 2:
The piezoelectric actuators perform preliminary alignment adjustments automatically before the bonding operation begins. By pre-positioning the ejector pin accurately using the actuators, the system eliminates the need for time-consuming manual alignment monitoring and adjustments during the actual bonding process, thus maintaining precision while reducing time loss.
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
Enables rapid and accurate alignment of the ejector pin with the pick-and-place tool, improving die detachment precision and throughput by allowing for quick adjustments within 20 ms and a range of 150 μm, even with dual bond arms, thereby addressing alignment issues and thermal expansion impacts.
Implementation Method 1
the positioning device further comprising at least one piezoelectric actuator; and at least one flexure connecting the piezoelectric actuator and the movable table, the flexure being operatively responsive to actuation by the piezoelectric actuator
Implementation Method 2
at least one flexure connecting the piezoelectric actuator and the movable table, the flexure being operatively responsive to actuation by the piezoelectric actuator to force the movable table and ejector shaft to move
Data Source
AI summary
A die detachment apparatus for detaching a die from an adhesive tape on which the die is mounted includes a pick-and-place tool movable along a pick-up axis for picking up the die from the adhesive tape and a die ejector comprising an ejector shaft including an ejector pin. The ejector pin is movable parallel to the pick-up axis to raise the die from the adhesive tape to facilitate pick-up of the die by the pick-and-place tool. At least one movable table to which the ejector shaft is operatively coupled is actuable by at least one piezoelectric actuator which is connected to the movable table via a flexure. Actuation by the piezoelectric actuator forces the movable table and ejector shaft to move in directions which are perpendicular to the pick-up axis for alignment of the ejector pin with the die pick-up tool along the pick-up axis.