Cyclic Silazane Surface Treatment for TiN Pattern Collapse

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current surface treatment agents, such as silylation agents like hexamethyldisilazane, fail to achieve sufficient hydrophobization of TiN or SiN substrate surfaces, leading to pattern collapse during the drying process in semiconductor manufacturing due to insufficient reduction of surface tension forces between inorganic patterns.

Innovation Solution

A surface treatment agent containing cyclic silazane compounds, specifically cyclic disilazane and trisilazane compounds, is used to effectively hydrophobize TiN or SiN substrate surfaces, reducing the surface tension forces and preventing pattern collapse by increasing the contact angle of the rinse liquid.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional silylation agents (HMDS, DMATMS) are used for surface treatment, then the process is simple and well-established, but the hydrophobization effect on TiN or SiN surfaces is insufficient, leading to pattern collapse

Engineering Contradiction:
Improvepattern stabilityVSAvoidsurface treatment effectiveness
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent changes the chemical structure parameter of the silylation agent from linear (HMDS, DMATMS) to cyclic (1,3,5-trimethyl-1,3,5-trivinylcyclotrisilazane), which fundamentally alters the reactivity and bonding characteristics with TiN and SiN surfaces, achieving sufficient hydrophobization that prevents pattern collapse

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent combines multiple functional groups in the cyclic silazane compound (vinyl groups for crosslinking, methyl groups for hydrophobicity, cyclic structure for stability) to create a surface treatment agent that simultaneously achieves strong adhesion, high hydrophobicity, and thermal stability on TiN and SiN surfaces

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If the surface tension of rinse liquid is reduced by adding surfactants, then the surface tension decreases, but pattern collapse prevention is insufficient

Engineering Contradiction:
Improvesurface tension forceVSAvoidpattern collapse prevention
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent applies surface treatment with cyclic silazane compound before the rinsing process, creating a hydrophobic surface layer that prevents rinse liquid from wetting the inorganic pattern surface, thereby eliminating capillary forces during drying and preventing pattern collapse

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The cyclic silazane compound acts as an intermediary layer between the inorganic pattern and the rinse liquid, creating a hydrophobic barrier that prevents direct contact between the rinse liquid and the pattern surface, thereby eliminating surface tension-induced collapse

Inventive Principle:
Principle #24Intermediary (Mediator)

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 use of cyclic silazane compounds in the surface treatment agent significantly increases the hydrophobicity of TiN and SiN surfaces, preventing pattern collapse by reducing the force acting between inorganic patterns during the drying process, as demonstrated by increased contact angles measured in examples.

Implementation Method 1

hydrophobization treatment of a substrate surface... contains a cyclic silazane compound... significantly increases the hydrophobicity of TiN and SiN surfaces

Methodology Applied
Scientific EffectHydrophobization: Hydrophobe

Implementation Method 2

reducing the surface tension forces and preventing pattern collapse by increasing the contact angle of the rinse liquid

Methodology Applied
Scientific EffectSurface tension reduction: Surface Tension

Data Source

PatentUS8410296B2Surface treatment agent and surface treatment method
Publication Date: 2013.04.02 TOKYO OHKA KOGYO CO LTD

AI summary

Provided are a surface treatment agent for which hydrophobization to a high degree is possible even in a case of the material of a substrate surface being TiN or SiN, and surface treatment method using such a surface treatment agent. The surface treatment agent according to the present invention contains a cyclic silazane compound. As this cyclic silazane compound, a cyclic disilazane compound such as 2,2,5,5-tetramethyl-2,5-disila-1-azacyclopentane and 2,2,6,6-tetramethyl-2,6-disila-1-azacyclohexane and a cyclic trisilazane compound such as 2,2,4,4,6,6-hexamethylcyclotrisilazane and 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane are preferred. In the surface treatment, a substrate surface is exposed to a surface treatment agent according to the present invention, and the substrate surface is hydrophobized.