Plasma Processing Electrode Plates DC Sputtering for Deposit Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During plasma etching of hard-to-etch materials with high vapor pressure, deposits often form on the inner walls of plasma processing apparatuses and are difficult to remove, leading to re-deposition on wafers and contamination issues.
Innovation Solution
A plasma processing apparatus with a gas supply system, plasma source, support, exhaust system, electrode plates, insulators, and a controller that applies a DC voltage to electrode plates independently to sputter and remove deposits using ions from the processing gas, particularly using Ar gas, both during and after etching processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If plasma etching is performed on hard-to-etch materials with high vapor pressure, then etching capability is improved, but deposits form on inner walls and are difficult to remove
Solution Approach 1:
The patent converts the harmful deposits formed during etching of hard-to-etch materials into removable sputtered particles by applying DC voltage to electrode plates. The DC voltage generates ions that sputter the deposits, transforming the contamination problem into a controllable removal process that maintains etching effectiveness while preventing re-deposition on wafers
Solution Approach 2:
The patent changes the electrical parameter of the electrode plates by applying DC voltage during or after the etching process. This parameter change enables the electrode plates to generate ions through sputtering, which actively removes deposits from inner walls that would otherwise be difficult to eliminate, thus resolving the contradiction between etching capability and deposit formation
2Object-generated harmful factors
If DC voltage is applied to electrode plates during etching, then deposits are removed by sputtering, but device complexity increases
Solution Approach 1:
The patent makes the electrode plates multi-functional by enabling them to serve both as structural components of the plasma processing apparatus and as active elements for deposit removal through DC voltage application. This universality allows the same component to perform multiple functions without adding separate dedicated removal mechanisms, thus limiting the increase in device complexity
Solution Approach 2:
The electrode plates perform self-service by using the plasma environment already present during etching to remove their own deposits through sputtering. The ions generated by the plasma and DC voltage combination automatically sputter deposits from the electrode surfaces, eliminating the need for separate cleaning systems and reducing overall device complexity
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
Effectively reduces deposits on the inner walls of the processing container by sputtering with ions, preventing re-deposition on wafers and ensuring cleaner etching processes even with hard-to-etch materials.
Implementation Method 1
a plasma source configured to excite the processing gas supplied from the gas supply system
Implementation Method 2
the DC voltage is supplied to each of the plurality of electrode plates during execution of the etching or after completion of the etching
Data Source
AI summary
An apparatus for plasma processing that performs an etching on a workpiece, includes: a container; a gas supply system for supplying a processing gas into the container; a plasma source for exciting the processing gas; a support for holding the workpiece inside the container; an exhaust system for exhausting an internal space of the container; electrode plates provided on an inner wall of the container; insulators for electrically insulating the electrode plates from each other; a DC power supply for independently applying a DC voltage to each of the electrode plates; and a controller for controlling the gas supply system, the plasma source, and the DC power supply. The controller controls the gas supply system, the plasma source, and the DC power supply such that the DC voltage is supplied to each electrode plate during execution of the etching or after completion of the etching.