Single-Wafer Cleaning Ionizer for Electrostatic Charge Neutralization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The miniaturization of patterns on semiconductor wafers has increased the importance of the cleaning process, where electrostatic charges can damage circuits and films during wafer cleaning, leading to defects.
Innovation Solution
A single-wafer-type cleaning apparatus equipped with an ionizer that generates ions using methods like corona, piezo high frequency alternating current, or X-ray to neutralize charged particles on the wafer, combined with a chuck system and chemical dispensing nozzles for effective cleaning and drying.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the cleaning process is performed to remove residues and contaminants from the wafer surface, then cleaning effectiveness is improved, but electrostatic charges can accumulate and damage circuits and films
Solution Approach 1:
The ionizer is positioned to emit ions onto the wafer surface before the cleaning chemicals are applied and before the wafer is removed from the cleaning apparatus. This preliminary neutralization of electrostatic charges prevents the accumulation of harmful charges that would otherwise damage circuits and films during the cleaning process, while still allowing effective cleaning to occur.
2Productivity
If the wafer is rotated at high speed for effective cleaning, then cleaning efficiency is improved, but electrostatic charges are generated and accumulated
Solution Approach 1:
The ionizer converts the electrostatic charges that are generated during high-speed wafer rotation into a beneficial effect by emitting ions that neutralize these charges. The harmful electrostatic accumulation is transformed into a controlled ion emission process that prevents damage while maintaining the high-speed rotation necessary for effective cleaning.
Solution Approach 2:
The ionizer acts as an intermediary between the rotating wafer and the cleaning chemicals. It neutralizes electrostatic charges on the wafer surface, preventing charge accumulation that would otherwise interfere with the cleaning process and potentially damage the wafer. This intermediary function allows high-speed rotation to proceed without generating harmful electrostatic effects.
3Reliability
If an ionizer is added to neutralize electrostatic charges, then defect reduction is improved, but device complexity increases
Solution Approach 1:
The ionizer is integrated into the existing cleaning apparatus structure, allowing it to perform multiple functions: neutralizing electrostatic charges on the wafer surface, working in conjunction with the cleaning chemicals, and operating during the high-speed rotation process. This multi-functionality reduces the need for separate dedicated systems while achieving defect reduction.
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 apparatus effectively neutralizes electrostatic charges on the wafer, reducing defect rates and ensuring the integrity of semiconductor devices during the manufacturing process.
Implementation Method 1
the ionizer may generate the ions using a corona method
Implementation Method 2
the ionizer may generate the ions using a corona method, a piezo high frequency alternating current (HF-AC) method
Implementation Method 3
the ionizer may generate the ions using a corona method, a piezo high frequency alternating current (HF-AC) method, or an X-ray method
Implementation Method 4
the chuck may include a non-rotating body disposed at a center of the chuck and a rotating body configured to surround the non-rotating body
Data Source
AI summary
A single-wafer-type cleaning apparatus is provided. The single-wafer-type cleaning apparatus is configured to be capable of controlling electrostatic charges generated due to rotating a wafer during a semiconductor cleaning process and a defect caused by the electrostatic charges. The cleaning process uses an ionizer mounted on a chuck.