Plasma Chamber Cleaning With a Smaller Dummy Substrate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The accumulation of foreign substances in a plasma chamber during plasma etching processes can lead to arcing phenomena due to insufficient removal after in-situ dry cleaning, especially when the substrate stage receives a small amount of ions, causing residual foreign substances to remain and potentially cause damage.
Innovation Solution
A method involving a plasma processing apparatus that uses a dummy substrate with a smaller diameter than the original substrate to perform a plasma dry cleaning process, where the dummy substrate is aligned using lift pins to expose the focus ring of the substrate support to plasma, effectively removing foreign substances and preventing arcing while protecting the electrostatic chuck.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a substrate with standard diameter is used for plasma etching, then the etching process can be performed, but foreign substance accumulates on the focus ring and electrostatic chuck, causing arcing phenomenon
Solution Approach 1:
A dummy substrate is introduced as an intermediary object during the plasma cleaning process. This dummy substrate serves as a mediator that protects the electrostatic chuck and focus ring from direct plasma exposure while still allowing plasma to clean foreign substances from its own surface and the exposed focus ring areas, thereby preventing arcing without damaging critical components
Solution Approach 2:
The dummy substrate acts as a simplified copy or placeholder that replicates the function of protecting the chamber components during plasma cleaning. Instead of using the actual substrate or exposing the electrostatic chuck directly, the dummy substrate copy performs the protective function while enabling effective plasma cleaning of foreign substances
2Object-affected harmful factors
If plasma is applied to clean the chamber, then foreign substance is removed, but the electrostatic chuck may be damaged by plasma exposure
Solution Approach 1:
The dummy substrate serves as a protective intermediary between the plasma and the electrostatic chuck. It allows plasma to be applied for cleaning purposes while the dummy substrate absorbs the plasma exposure, preventing direct contact with and potential damage to the electrostatic chuck
Solution Approach 2:
The dummy substrate is a consumable component designed to be used temporarily during cleaning cycles. It is intentionally exposed to plasma to protect more valuable components like the electrostatic chuck, and can be replaced when worn or contaminated, serving as a sacrificial protective element
3Object-affected harmful factors
If a dummy substrate with smaller diameter is used, then the focus ring is exposed to plasma for cleaning, but misalignment may occur during loading
Solution Approach 1:
The cleaning function is segmented into two parts: the dummy substrate handles the cleaning of the focus ring and central areas, while the smaller size allows it to be positioned without requiring perfect alignment with the electrostatic chuck. This segmentation of functions allows the dummy substrate to be smaller and less critical for alignment precision
Solution Approach 2:
The dummy substrate is pre-positioned on the substrate stage before the plasma cleaning process begins. Lift pins are used to preliminarily position and secure the dummy substrate in place, ensuring proper alignment before plasma exposure occurs, thereby preventing misalignment during the cleaning process
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 efficiently removes foreign substances from the plasma chamber, preventing arcing and ensuring proper alignment and protection of the electrostatic chuck, thereby maintaining the integrity of the semiconductor device manufacturing process.
Implementation Method 1
performing a plasma dry cleaning process on the dummy substrate to remove foreign substance in the plasma chamber
Implementation Method 2
the electrostatic chuck of the substrate stage may be protected from plasma
Data Source
AI summary
Provided is a method of manufacturing a semiconductor device. The method comprises loading a substrate having a first diameter onto a substrate support within a plasma chamber, performing a plasma process on the substrate, unloading the substrate from the plasma chamber, loading a dummy substrate having a second diameter smaller than the first diameter onto the substrate support, and performing a plasma cleaning process on the dummy substrate to remove foreign substance in the plasma chamber.