Semiconductor Thin Film Ligand Removal via Electron Withdrawing Compound
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in semiconductor device manufacturing is the insufficient removal of ligands from thin films, which can increase the resistivity of metal films due to residual impurities, especially when forming films like titanium nitride, where strong bonds between main elements and ligands hinder pyrolysis and lead to impurity incorporation.
Innovation Solution
A method involving time-divisional gas supply sequences using a precursor gas, a compound with an electron withdrawing group (such as BCl3) to weaken the bond between the main element and ligands, followed by a reaction gas (like NH3) to desorb the ligands, enhancing their removal efficiency and preventing impurity introduction into the film.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a precursor gas is supplied to form a thin film, then the film can be formed on the substrate, but ligands remain as impurities in the film increasing resistivity
Solution Approach 1:
The film formation process is divided into multiple sequential steps: precursor supply, ligand removal using electron withdrawing compound, and reaction gas supply. This segmentation allows each step to optimize for its specific function, ensuring complete ligand removal while maintaining film quality.
Solution Approach 2:
An electron withdrawing compound is supplied before the reaction gas to pre-weaken the bonds between main elements and ligands. This preliminary action facilitates subsequent ligand removal and prevents impurity incorporation into the final film.
2Object-generated harmful factors
If pyrolysis is performed to remove ligands, then ligand removal occurs, but strong bonds between main elements and ligands prevent complete removal
Solution Approach 1:
An electron withdrawing compound acts as an intermediary substance that temporarily bonds to ligands, weakening the main element-ligand bonds. This intermediary facilitates ligand removal without requiring excessive energy that would damage the film structure.
Solution Approach 2:
The chemical environment is changed by introducing electron withdrawing compounds that alter the bond characteristics. This parameter change weakens the bond strength between main elements and ligands, enabling complete ligand removal through subsequent processing.
3Productivity
If multiple gases are supplied simultaneously, then the process time is reduced, but ligand removal efficiency decreases
Solution Approach 1:
The gas supply process is segmented into distinct temporal phases: precursor gas supply, electron withdrawing compound supply, and reaction gas supply. This time-divisional approach ensures optimal ligand removal efficiency while maintaining acceptable process throughput.
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 improves the ligand removal efficiency, reduces film resistivity, and forms high-quality thin films by ensuring the main element reacts effectively with the reaction gas while minimizing impurity incorporation.
Implementation Method 1
supplying a precursor gas to the substrate and causing precursor molecules, which are contained in the precursor gas and which contains a main element and ligands, to be adsorbed onto the substrate
Implementation Method 2
supplying a compound containing an electron withdrawing group to the substrate onto which the precursor molecules are adsorbed, and causing the compound containing the electron withdrawing group to be adsorbed to the ligands contained in the precursor molecules
Implementation Method 3
supplying a reaction gas to the substrate onto which the precursor molecules and the compound containing the electron withdrawing group are adsorbed, causing the ligands and the compound containing the electron withdrawing group to be desorbed from the substrate
Data Source
AI summary
A method of manufacturing a semiconductor device includes: forming a film on a substrate by time-divisionally and sequentially performing: (a) supplying a precursor gas to the substrate and causing precursor molecules, which are contained in the precursor gas and which contains a main element and ligands, to be adsorbed onto the substrate; (b) supplying a compound containing an electron withdrawing group to the substrate onto which the precursor molecules are adsorbed, and causing the compound containing the electron withdrawing group to be adsorbed to the ligands contained in the precursor molecules; and (c) supplying a reaction gas to the substrate onto which the precursor molecules and the compound containing the electron withdrawing group are adsorbed, causing the ligands and the compound containing the electron withdrawing group to be desorbed from the substrate, and causing the main element contained in the precursor molecules to react with the reaction gas.