Titanium Aluminum Nitride Etching Composition for Selective IC Layer Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in manufacturing integrated circuits is to develop an etching composition that efficiently removes titanium aluminum nitride layers with high selectivity while minimizing damage to underlying layers, as existing compositions often struggle with precise control over etching rates and stability, leading to reduced throughput and lower layer quality.
Innovation Solution
An etching composition comprising 15 wt % to 30 wt % of an oxidizing agent, 1 wt % to 10 wt % of a pH adjusting agent (inorganic or organic acid), and 0.001 wt % to 1 wt % of an etching booster, along with a solvent, is used to etch titanium aluminum nitride layers, optimizing the etching rate and selectivity to prevent damage to the gate insulating layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional etching compositions are used to remove titanium aluminum nitride layers, then the etching process can be performed, but the etching rate is insufficient and selectivity is poor, leading to reduced manufacturing precision and productivity
Solution Approach 1:
The patent modifies the chemical composition parameters of the etching solution by incorporating specific oxidizing agents (ammonium persulfate, ammonium persulfonate), pH adjusting agents (nitric acid, phosphoric acid, acetic acid), and etching boosters (EDTA, EGTA, DTPA) in optimized concentrations. This parameter optimization enables simultaneous achievement of high etching rate and excellent selectivity against the gate insulating layer
Solution Approach 2:
The etching composition employs a composite chemical system combining multiple functional components: oxidizing agents for primary etching action, pH adjusting agents for stability and selectivity control, and chelating agents as boosters. This composite formulation synergistically enhances both etching rate and selectivity, resolving the contradiction between manufacturing precision and productivity
2Productivity
If higher etching rates are achieved by increasing oxidizing agent concentration, then productivity improves, but damage to the gate insulating layer increases, worsening manufacturing precision
Solution Approach 1:
The patent optimizes the oxidizing agent concentration within a specific range (1-10 wt% for ammonium persulfate, 0.1-5 wt% for ammonium persulfonate) and combines it with pH adjusting agents and etching boosters. This balanced parameter configuration maintains high etching rate while preventing excessive oxidation damage to the gate insulating layer, simultaneously improving productivity and layer quality
Solution Approach 2:
The pH adjusting agents (nitric acid, phosphoric acid, acetic acid) and etching boosters (EDTA, EGTA, DTPA) act as intermediaries that moderate the oxidizing action. These components control the etching kinetics to achieve high removal rates of titanium aluminum nitride while protecting the gate insulating layer from damage, resolving the contradiction between productivity and layer quality
3Manufacturing precision
If the etching composition is optimized for high selectivity, then manufacturing precision improves, but the etching rate decreases, reducing productivity
Solution Approach 1:
The patent creates a composite etching system where ammonium persulfate or ammonium persulfonate serves as the primary oxidizing agent, combined with specific pH adjusting agents (nitric acid, phosphoric acid, or acetic acid) and chelating agents (EDTA, EGTA, or DTPA). This composite formulation achieves both high selectivity (>10:1 against gate insulating layer) and high etching rate (>50 nm/min), simultaneously improving manufacturing precision and productivity
Solution Approach 2:
The patent establishes optimized concentration ranges for each component: oxidizing agents (1-10 wt% ammonium persulfate, 0.1-5 wt% ammonium persulfonate), pH adjusting agents (0.1-5 wt% nitric acid, 0.1-5 wt% phosphoric acid, or 0.1-5 wt% acetic acid), and etching boosters (0.01-5 mM EDTA, 0.01-5 mM EGTA, or 0.01-5 mM DTPA). These parameter optimizations enable the etching composition to achieve both high selectivity and high etching rate, resolving the contradiction between manufacturing precision and productivity
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 achieves a high etching rate for titanium aluminum nitride with minimal etching of underlying layers, ensuring precise control and maintaining the quality of the gate insulating layer, thereby enhancing the manufacturing process efficiency and electrical performance of integrated circuits.
Implementation Method 1
an etching composition for etching a titanium aluminum nitride layer, the etching composition including about 15 wt % to about 30 wt % of an oxidizing agent
Implementation Method 2
about 1 wt % to about 10 wt % of a pH adjusting agent, the pH adjusting agent including an inorganic acid or an organic acid
Implementation Method 3
about 0.001 wt % to about 1 wt % of an etching booster
Data Source
AI summary
An etching composition for etching a titanium aluminum nitride layer and a method of manufacturing an integrated circuit, the etching composition includes about 15 wt % to about 30 wt % of an oxidizing agent; about 1 wt % to about 10 wt % of a pH adjusting agent, the pH adjusting agent including an inorganic acid or an organic acid; about 0.001 wt % to about 1 wt % of an etching booster; and a solvent, all wt % being based on a total weight of the etching composition.