Substrate Etching Liquid Chemistry for Fine Thin-Layer Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As first layers, such as interlayer films, become smaller and thinner, it becomes increasingly difficult to properly etch them due to decreased etching rates.
Innovation Solution
Incorporating molecular iodine (I2) and triiodide ions (I3−) into the etching liquid to enhance the etching process, ensuring adequate etching of the first layer even when it is small.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the first layer is made smaller and thinner to achieve finer patterns, then the pattern fineness is improved, but the etching rate decreases
Solution Approach 1:
The patent changes the chemical parameters of the etching liquid by adding iodide and molecular iodine to create a mixed liquid with enhanced etching capability. This parameter change allows the etching process to maintain high rates even on smaller, thinner first layers, thus resolving the contradiction between pattern fineness and etching rate
Solution Approach 2:
The patent introduces molecular iodine as an intermediary substance that facilitates the etching process. The molecular iodine acts as a mediator between the etching liquid and the first layer, enhancing the etching reaction efficiency and maintaining high etching rates for fine patterns
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
The method effectively etches the first layer by leveraging the etching assistance provided by molecular iodine (I2) and triiodide ions (I3−), maintaining etching efficiency despite the reduced size of the first layer.
Implementation Method 1
The iodide ion (I−) is a monovalent monoatomic anion composed of one iodine atom. When the iodide ions (I−) change to at least one of molecular iodine (I2) and triiodide ions (I3−), the amount of the iodide ions (I−) in the substrate processing liquid decreases. The present inventors have found that the molecular iodine (I2) assists the etching of the first layer. The present inventors have found that the triiodide ions (I3−) assist etching of the first layer.
Data Source
AI summary
The present invention relates to a substrate processing method, a substrate processing apparatus, and a substrate processing liquid. In the substrate processing method, a substrate W including a first layer G is processed. A second mixed liquid P2 contains an etching liquid and iodide ions (I−). The substrate processing method includes a first adjustment step and an etching step. In the first adjustment step, at least one of oxygen and ozone is added to the second mixed liquid P2. In the etching step, the second mixed liquid P2 adjusted in the first adjustment step is supplied to the substrate W. In the etching step, the first layer G is etched.