Phosphonic Acid Tungsten CMP Cleaning Composition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing cleaning agents for semiconductor substrates after chemical mechanical polishing (CMP) do not adequately inhibit the dissolution of tungsten-containing layers, leading to potential corrosion and reliability issues in semiconductor devices.
Innovation Solution
A surface treatment composition comprising a phosphonic acid compound with two or more nitrogen atoms and water, with a pH of 6 or less, is used to effectively inhibit the dissolution of tungsten layers by forming a stable complex with the tungsten surface, preventing hydration and corrosion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a phosphonic acid-based cleaning composition with pH more than 6 and less than 7 is used to clean semiconductor substrate after CMP, then foreign materials (abrasive fine grains) can be removed, but the dissolution inhibition effect of tungsten layer is insufficient
Solution Approach 1:
The patent changes the pH parameter from above 6 to 6 or less, and modifies the phosphonic acid compound structure to include two or more nitrogen atoms. This parameter change resolves the contradiction by achieving both effective foreign material removal and sufficient tungsten layer dissolution inhibition simultaneously.
Solution Approach 2:
The patent uses a composite cleaning composition containing phosphonic acid compound with two or more nitrogen atoms combined with specific additives. This composite approach enhances the dual functionality of removing foreign materials while effectively inhibiting tungsten layer dissolution.
2Manufacturing precision
If existing cleaning agents are used to remove foreign materials from semiconductor substrate, then cleaning is achieved, but corrosion of tungsten-containing layer occurs
Solution Approach 1:
The patent converts the potentially harmful dissolution effect on tungsten layer into a beneficial controlled process by using phosphonic acid compound with two or more nitrogen atoms at pH 6 or less. This composition selectively removes foreign materials while the phosphonic acid compound forms protective complexes with tungsten, converting the harmful corrosion into a controlled and beneficial surface treatment.
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 composition significantly reduces the etching rate of tungsten layers and maintains surface smoothness, effectively addressing the dissolution and corrosion issues while removing foreign materials from the semiconductor substrate.
Implementation Method 1
the above-described problems can be solved by using a composition for surface treatment including: a specific phosphonic acid compound; and water, and having a pH within a specific range
Implementation Method 2
there was a problem that an effect of inhibiting corrosion (dissolution) of the tungsten layer was not sufficient
Data Source
AI summary
The present invention relates to a composition for surface treatment including: a phosphonic acid compound containing two or more nitrogen atoms; and water, wherein the pH is 6 or less, and the composition for surface treatment is used for treating a surface of a polishing-completed object to be polished having a tungsten-containing layer. According to the present invention, there is provided a means capable of inhibiting dissolution of the tungsten-containing layer provided on a polishing-completed object to be polished when a surface treatment is performed.