Phosphoric Acid Ester Surface Treatment for ALD Selectivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surface treatment methods fail to selectively render metal regions more water-repellent than insulator regions on semiconductor substrates, which is essential for region-selective film formation in atomic layer deposition (ALD) processes.
Innovation Solution
A surface treatment agent comprising a phosphorus compound with a specific structure, such as HO—P(═O)R1R2, and an organic solvent is used to treat substrate surfaces with both metal and insulator regions, increasing the water contact angle of the metal region by 10° or more compared to the insulator region, thereby suppressing water repellency of the insulator region and enhancing the metal region's water repellency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional surface treatment methods (e.g., dodecylphosphonic acid or octadecyl phosphonic acid) are used, then metal substrates can be rendered water-repellent, but the selectivity between metal substrates and insulating substrates is insufficient
Solution Approach 1:
The patent applies local quality by using a surface treatment agent containing a phosphoric acid ester compound that selectively interacts with metal surfaces. The compound forms a monolayer on metal regions through chemisorption, creating water-repellent properties specifically on metal surfaces while leaving insulator regions unaffected. This achieves high selectivity between metal and insulator regions, enabling region-selective water repellency enhancement.
2Productivity
If water repellency is enhanced on metal regions, then film deposition can be controlled on metal surfaces, but insulator regions may also become water-repellent, reducing deposition selectivity
Solution Approach 1:
The patent changes the chemical parameter of the surface treatment agent by using a phosphoric acid ester compound with specific molecular structure and properties. This compound has selective affinity for metal surfaces through phosphorus-metal bonding, creating a water-repellent monolayer on metal regions with contact angles of 100° or more, while maintaining hydrophilic insulator regions. This parameter change ensures that subsequent ALD film deposition occurs selectively on insulator regions, achieving both film deposition control and deposition selectivity.
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 solution allows for selective water repellency enhancement of metal regions while maintaining or reducing water repellency of insulator regions, enabling more controlled film deposition in ALD processes by preventing film material adsorption on the metal regions, thus allowing for thicker film formation on insulator regions.
Implementation Method 1
the surface treatment agent including a phosphorus compound (P) having a specific structure... such that a water contact angle of the metal region is higher than a water contact angle of the insulator region adjacent to the metal region by 10° or more through the reaction between the compound (P) and the regions
Implementation Method 2
the surface treatment agent including a phosphorus compound (P) having a specific structure, and an organic solvent (S)
Data Source
AI summary
A surface treatment agent including a compound represented by the general formula HO—P(═O)R1R2 in which R1 and R2 are each independently bonded to the phosphorus atom and are each independently a hydrogen atom, an alkyl group, a fluorinated alkyl group, or an aromatic hydrocarbon group which may have a substituent, provided that R1 and R2 are not hydrogen atoms at the same time, and an organic solvent.