Substrate Etching Sequence for Metal Fluoride Residue Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate processing methods struggle with residue removal, particularly metal-containing residues, which can lead to etching damage and inefficiencies.
Innovation Solution
A method involving etching a silicon-containing film with a fluorine-containing gas plasma and then removing the residue using a second process gas different from the first, such as a chlorine-containing gas, without generating plasma, to selectively remove metal-containing residues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a fluorine-containing gas plasma is used to etch the silicon-containing film, then the etching efficiency is improved, but metal-containing residues are generated on the substrate
Solution Approach 1:
The patent converts the harmful metal-containing residues into removable metal fluorides by introducing a fluorine-containing gas in a second plasma treatment step. The fluorine reacts with the metal residues to form volatile metal fluorides that can be easily removed, transforming the harmful byproduct into a removable compound.
Solution Approach 2:
The patent changes the plasma parameters by switching from a first plasma process (optimized for silicon etching) to a second plasma process (optimized for residue removal). This involves changing the process gas composition and plasma conditions to selectively remove metal residues without damaging the silicon film.
2Object-generated harmful factors
If conventional methods are used to remove residues, then the substrate is cleaned, but etching damage occurs to the silicon-containing film
Solution Approach 1:
The patent applies different plasma treatments to different parts of the substrate: the first plasma process selectively etches the silicon-containing film while leaving the metal residues intact, and the second plasma process selectively removes the metal residues without affecting the silicon film. This localized selectivity is achieved through optimized plasma parameters and gas composition.
3Object-generated harmful factors
If multiple processing steps are added to remove residues, then the cleaning effectiveness is improved, but the process complexity increases
Solution Approach 1:
The patent combines the residue removal function with the existing plasma etching process by adding a second plasma treatment step using fluorine-containing gas. This integrated approach eliminates the need for separate cleaning steps and additional equipment, as both etching and residue removal are achieved within the same plasma processing system.
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 residues without causing further etching damage, promoting a cleaner and more efficient substrate processing.
Implementation Method 1
etching the silicon-containing film with plasma generated from a first process gas including a fluorine-containing gas
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In one example embodiment, a substrate processing method includes (a) providing a substrate including a silicon-containing film and a metal-containing film on the silicon-containing film, the metal-containing film including at least one opening; (b) etching the silicon-containing film with plasma generated from a first process gas including a fluorine-containing gas; and (c) removing a residue generated in the (b) by supplying a second process gas different from the first process gas, the residue including a metal and fluorine included in the metal-containing film.