Semiconductor Wafer Cleaning Combining Batch and Single-Wafer Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor wafer cleaning methods, either batch or single wafer cleaning, fail to achieve optimal results due to cross-contamination in batch cleaning and inefficiencies with high-temperature chemical solutions in single wafer cleaning, necessitating a combination of both approaches to effectively remove organics, particles, and film material while maintaining cost-effectiveness.
Innovation Solution
A method and apparatus that involves processing wafers in a first tank with chemical solution, then in a second tank with liquid, while keeping them in a wet status, followed by single wafer cleaning and drying, utilizing multiple robots and turnover mechanisms to manage wafer handling and chemical solution recycling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If batch cleaning is used to clean multiple wafers simultaneously, then cleaning efficiency is improved, but cross-contamination occurs between wafers
Solution Approach 1:
The batch cleaning process is segmented into multiple independent cleaning zones (first cleaning zone, second cleaning zone, third cleaning zone) with separate chemical solution systems. Each zone handles specific cleaning functions, preventing cross-contamination while maintaining batch processing efficiency. The turnover mechanism further segments wafer handling into discrete transfer steps between zones.
Solution Approach 2:
A turnover mechanism acts as an intermediary device between cleaning zones, enabling controlled transfer of wafers while maintaining separation of cleaning environments. This intermediary mechanism allows efficient wafer movement without direct contact between wafers from different cleaning batches, preventing cross-contamination.
2Object-affected harmful factors
If single wafer cleaning is used to avoid cross-contamination, then cleaning quality is improved, but cleaning efficiency decreases
Solution Approach 1:
The invention merges the advantages of single wafer cleaning (contamination control) with batch cleaning (efficiency) by processing multiple wafers simultaneously through separate cleaning zones. Each wafer receives individualized cleaning treatment in its own chemical solution environment, while the overall system maintains high throughput by handling multiple wafers in parallel across different zones.
Solution Approach 2:
The cleaning apparatus performs multiple functions within a single integrated system: it provides batch processing capability, maintains separate chemical solution environments for each cleaning stage, enables controlled wafer transfer, and ensures comprehensive cleaning of multiple contaminants. This multi-functional design achieves both high efficiency and contamination prevention.
3Object-affected harmful factors
If high temperature chemical solution is used to remove organics, then cleaning effectiveness is improved, but solution recycling becomes difficult
Solution Approach 1:
The chemical solution system is segmented into multiple independent zones with different temperature and composition requirements. The first cleaning zone uses high temperature SPM for effective organic removal, while subsequent zones use lower temperature solutions that are easier to recycle. This segmentation allows each zone to be optimized for its specific function without compromising overall solution recyclability.
Solution Approach 2:
The system recovers and recycles chemical solutions from each cleaning zone separately. High temperature SPM from the first zone is recovered and reused within that zone, while solutions from subsequent zones are recycled independently. This selective recovery approach maintains cleaning effectiveness while reducing overall chemical consumption and improving sustainability.
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 approach effectively removes organics and particles, recycles high-temperature chemical solutions, controls acid mist, and ensures easy removal of contaminants by maintaining wafers in a wet status throughout the process, enhancing the cleaning efficiency and reducing costs.
Implementation Method 1
The main chemical solution for cleaning the wafer includes, for example SC1, BOE and SPM which is a mixture of H2SO4 and H2O2
Implementation Method 2
the temperature of SPM is higher than 90° C. and the SPM is used for removing the residual photoresist and organics
Implementation Method 3
drying said wafer
Data Source
AI summary
A method and apparatus for cleaning semiconductor wafer, combining batch cleaning and single wafer cleaning together. The method includes: taking at least two wafers from a cassette in a load port and putting said wafers into a first tank filled with chemical solution; after processing said wafers in the first tank, taking said wafers out of the first tank and keeping said wafers wet; putting said wafers into a second tank filled with liquid; after processing said wafers in the second tank, taking said wafers out of the second tank and keeping said wafers wet; putting one of said wafers on a chuck inside a single wafer cleaning module; rotating the chuck while applying chemical solution on said wafer; applying deionized water on said wafer; drying said wafer; taking said wafer out of the single wafer cleaning module and putting said wafer back to the cassette in the load port.