Swing Spray Head for Semiconductor Wafer Cleaning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In the semiconductor industry, the increased diameter of wafers with copper interconnections leads to significant differences in tangential velocity between the center and edge during cleaning, resulting in larger liquid backsplash and ineffective removal of photoresist and residues at the wafer edge due to vertical chemical liquid spraying.
Innovation Solution
A swing spray device with a spray arm, spray head, and driving unit, where the spray head is hinged and controlled by an air cylinder to swing, allowing for vertical spraying at the center and inclined spraying at the edge, reducing backsplash and enhancing cleaning efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If chemical liquids are vertically sprayed to the wafer surface during high-speed rotation, then the cleaning process can be performed, but large liquid backsplash occurs at the wafer edge due to high tangential velocity, degrading cleaning effectiveness
Solution Approach 1:
The spray head is made movable with respect to the spray arm through a driving unit, allowing the spray direction to be dynamically adjusted. The spray head can swing between a first direction (perpendicular to wafer surface) and a second direction (inclined relative to wafer surface), enabling adaptive response to varying tangential velocities across the wafer surface.
Solution Approach 2:
Different spray directions are applied to different regions of the wafer surface. The spray head sprays in a first direction for the wafer center region and swings to spray in a second direction for the wafer edge region, providing locally optimized cleaning for each area based on its specific tangential velocity characteristics.
2Object-affected harmful factors
If the spray head moves at lower speed to reduce backsplash, then liquid collision is gentler, but dissolving photoresist and residues in the grooves at the wafer edge becomes difficult
Solution Approach 1:
The spray head provides locally adapted spray characteristics: at the wafer edge, it swings to an inclined spray direction that reduces backsplash while maintaining sufficient cleaning force, and adjusts spray parameters to effectively dissolve and remove photoresist and residues from deep grooves without causing excessive backsplash.
3Productivity
If the wafer diameter is increased to 300 mm to accommodate copper interconnections, then device capacity is improved, but the difference in tangential velocity between center and edge becomes significant, causing cleaning non-uniformity
Solution Approach 1:
The spray head is made dynamically adjustable through a driving unit that enables swinging motion. This allows the spray direction to be continuously adjusted during the cleaning process, compensating for the velocity differences across the large 300 mm wafer surface and maintaining cleaning uniformity.
Solution Approach 2:
The system applies different spray directions to different radial positions on the wafer. The spray head swings to provide inclined spray at the edges while maintaining perpendicular spray at the center, creating locally optimized cleaning conditions across the entire large wafer surface.
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 swing spray device effectively removes residues from both the center and edge of the wafer by compensating for velocity differences, minimizing backsplash and improving cleaning effectiveness by adjusting the spray direction based on tangential velocity, ensuring thorough cleaning of deep grooves.
Implementation Method 1
the driving unit is an air cylinder comprising a piston rod connected with the spray head; the spray head is swung by pushing the piston rod out of the air cylinder through the action of compressed air
Data Source
AI summary
The present invention relates to the field of semiconductor manufacturing technology, more particularly to a swing spray device of a cleaning apparatus and a cleaning method. The swing spray device comprises a spray arm, a spray head and a driving unit. The spray head is connected with the spray arm, and is controlled to swim by the driving unit. The spray head is hinged with the spray arm to form a first hinge joint. The driving unit is an air cylinder; the piston rod of the air cylinder is connected with the spray head. The piston rod is hinged with the spray head to form a second hinge joint. Therefore, the better cleaning effects can be achieved both in the center and the edge of the wafer.