Cleaning Fluid Guide Device for Wafer Thickness Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor integrated circuit manufacturing, the repeated wet cleaning of wafer backside leads to uneven thickness, causing defects and yield reduction due to the consistent starting point of cleaning fluid spraying from the center, which worsens with each cleaning process.
Innovation Solution
A cleaning fluid guide device with a nozzle and electric field generated by positive and negative voltage ends on either side, allowing the included angle between the cleaning fluid and wafer backside to be controlled, preventing consistent starting points and reducing mechanical component wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the cleaning fluid spraying always starts from the center of the wafer backside, then the cleaning process is simple and consistent, but the wafer backside becomes uneven in thickness with the center being relatively thin and the edge relatively thick
Solution Approach 1:
The patent applies asymmetry by positioning the nozzle at an offset location rather than at the center of the wafer backside. This asymmetric positioning ensures that the cleaning fluid spray pattern creates a more uniform thickness distribution across the wafer surface, preventing the center from becoming excessively thin while maintaining process simplicity without requiring complex mechanical movement mechanisms.
2Manufacturing precision
If a mechanical arm is added to adjust the nozzle position to different starting positions, then the wafer backside thickness uniformity is improved, but mechanical component wear occurs leading to particle generation and further contamination
Solution Approach 1:
The patent replaces the mechanical arm positioning system with a fixed nozzle structure. Instead of using mechanical components that move and wear, the solution employs a stationary nozzle at an optimized offset position that achieves uniform wafer thickness through its fixed geometric relationship with the wafer, thereby eliminating particle generation from mechanical wear.
Solution Approach 2:
The patent segments the cleaning function by separating the positioning function (achieved through fixed geometric design) from the cleaning action (performed by the nozzle). The nozzle is positioned at a specific offset distance from the wafer center, creating distinct functional zones that achieve uniform cleaning without requiring mechanical movement or adjustment mechanisms.
3Adaptability or versatility
If a mechanical arm with transmission and control structures is added to change nozzle position, then the starting position of cleaning fluid spraying can be varied, but the device complexity increases and accurate control becomes difficult
Solution Approach 1:
The patent extracts the positioning function from the cleaning system by using a fixed, pre-determined nozzle offset position. Instead of incorporating complex transmission and control structures within the device, the solution takes out the need for active positioning mechanisms and relies on the fixed geometric relationship between the nozzle and wafer center, achieving position variability through design rather than mechanical adjustment.
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 even wafer thickness by varying the starting position of the cleaning fluid, improving semiconductor device yield and reducing particle contamination from mechanical movements.
Implementation Method 1
a positive voltage end and a negative voltage end, wherein the positive voltage end and the negative voltage end are located on the wafer backside and respectively located on both sides of the nozzle, and are used to apply an electric field to the cleaning fluid sprayed by the nozzle
Data Source
AI summary
The present application relates to semiconductor integrated circuit manufacturing equipment, in particular to a cleaning fluid guide device for wet cleaning equipment, wherein a positive voltage end and a negative voltage end are provided on both ends of a nozzle to apply an electric field to a cleaning fluid sprayed by the nozzle, and the electric field guides the cleaning fluid to form an included angle θ between the cleaning fluid and a wafer backside, such that spraying of the cleaning fluid does not always start from the center of the wafer backside, avoiding the problem that the center of the wafer backside is relatively thin while the edge thereof is relatively thick after a plurality of repeated wet cleaning processes, and thereby improving the yield of semiconductor devices.