Carrier Dechucking with Ion Neutralization for Solder Ball Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The separation of substrates with temporarily attached solder balls from a placement table often results in alignment issues due to static electricity-induced peeling electrification, leading to a decrease in reliability.
Innovation Solution
A carrier dechucking system that includes a support film attached to the substrate, a placement table, lifting pins, and an ionizer, controlled to move the substrate in a stepwise manner and eject ions to neutralize static electricity, maintaining attractive force between the substrate and the table to prevent solder ball deviation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the substrate is separated from the placement table after solder ball attachment, then the substrate can be moved to the reflow process, but static electricity causes solder balls to deviate from aligned positions
Solution Approach 1:
The ionizer is activated before substrate separation to preemptively neutralize static electricity charges on the support film. This preliminary action prevents the buildup of electrostatic forces that would otherwise cause solder ball deviation during the separation process, ensuring alignment precision is maintained while enabling continuous productivity
Solution Approach 2:
Ions generated by the ionizer act as an intermediary substance between the support film and the placement table during separation. These ions neutralize the static electricity charges on the support film, serving as a mediating mechanism that prevents direct electrostatic interaction between the substrate and placement table, thereby preventing solder ball deviation
2Productivity
If the substrate is separated quickly from the placement table, then productivity is improved, but static electricity effects worsen causing solder ball shift
Solution Approach 1:
The ionizer is activated before and during the separation process to preemptively neutralize static electricity charges. This allows the substrate to be separated at high speed without experiencing the harmful effects of peeling electrification, as the ions are already present to counteract charge buildup during the rapid separation
Solution Approach 2:
The ionizer operates continuously during the separation process to maintain neutralization of static electricity charges throughout the entire separation duration. This continuous action ensures that even during rapid separation, the support film remains free from accumulating static charges that would cause solder ball deviation, maintaining reliability throughout the process
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
Effectively suppresses solder ball shift caused by static electricity, maintaining alignment and reliability during the separation process.
Implementation Method 1
at least one ionizer configured to eject ions to the lower surface of the support film
Implementation Method 2
controller configured to control the at least one ionizer such that static electricity charged on the support film is removed
Data Source
AI summary
A carrier dechucking system includes a work carrier including a substrate having a first surface, an opposite second surface with a support film attached, and a ring frame surrounding the substrate. The work carrier is placed on a placement table having a support surface on which a lower surface of the support film is maintained, lifting pins configured to move the work carrier, an ionizer configured to eject ions to the lower surface, and a controller. The controller is configured to control the lifting pins to move the work carrier from the support surface to first and second levels, and to control the ionizer to remove static electricity charged on the support film from the support surface to the first level. At the first level, a surface voltage of the first surface of the substrate is lower than a surface voltage of the lower surface of the support film.