Current Plates for Uniform Chemical Flow in Substrate Processing
Solution Overview
Problem
In batch substrate processing devices, variations in chemical flow velocity lead to uneven etching rates and silica deposition on semiconductor substrates due to non-uniform chemical circulation, causing inconsistencies in processing results.
Innovation Solution
The implementation of current plates in specific regions of the processing tank obstructs chemical flow, ensuring uniform downward flow along the tank's sidewalls, thereby maintaining consistent chemical concentration and reducing etching rate variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If chemical circulation is performed in the processing tank, then chemical concentration uniformity is improved, but flow velocity variation causes etching rate inconsistency
Solution Approach 1:
The patent introduces flow control holes at specific locations on the lifter to create localized flow regulation. By positioning holes at particular regions (e.g., corners or edges where flow velocity varies), the system applies different flow control characteristics to different areas, ensuring uniform chemical distribution while maintaining consistent etching rates across all substrates.
Solution Approach 2:
The lifter with flow control holes acts as an intermediary between the chemical circulation system and the substrates. It mediates the chemical flow by introducing flow control holes that regulate how chemicals reach the substrates, thereby decoupling the circulation system's flow variations from the actual etching process and ensuring uniform processing.
2Productivity
If chemical flow velocity varies in different regions, then circulation efficiency is improved, but silica deposition occurs in low velocity regions
Solution Approach 1:
The patent applies local flow control by positioning holes at specific locations on the lifter where flow velocity is insufficient. This localized intervention ensures that chemicals are properly delivered to low-velocity regions without compromising the overall circulation efficiency, preventing silica deposition while maintaining productive chemical flow.
Solution Approach 2:
The patent converts the harmful effect of low flow velocity (which causes silica deposition) into a beneficial flow pattern. By introducing flow control holes, the system creates targeted flow paths that convert stagnant, harmful flow into useful, uniform chemical delivery, transforming a problem area into a controlled processing zone.
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 configuration ensures consistent flow velocities across the substrate array, minimizing variations in etching rates and silica deposition, thereby enhancing processing uniformity and substrate quality.
Implementation Method 1
The implementation of current plates in specific regions of the processing tank obstructs chemical flow, ensuring uniform downward flow along the tank's sidewalls
Implementation Method 2
the substrate processing device supplies the chemical from nozzles in the processing tank, recovers the chemical flowing over the upper end portion of the processing tank, performs processing such as removal of impurities, and then supplies again the chemical from the nozzles to the processing tank
Data Source
AI summary
A substrate processing device according to the present embodiment includes a processing tank configured to be capable of accumulating a liquid. A conveyer can array a plurality of semiconductor substrates in such a manner that front surfaces of the semiconductor substrates face a substantially horizontal direction, and transport the semiconductor substrates into the processing tank. A plurality of liquid suppliers can supply the liquid toward an inside of the processing tank from a lower portion of the processing tank. A plurality of current plates are arranged on at least either one end side or the other end side of an array of the semiconductor substrates. The current plates are provided in a first gap region above the semiconductor substrates in gaps between the conveyer and a sidewall of the processing tank on both sides of the conveyer as viewed from an array direction of the semiconductor substrates.