Thin Inorganic Film Deposition via Tridentate Metal Precursor

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for generating thin inorganic films on substrates face challenges in achieving high quality and reproducibility while minimizing precursor decomposition and allowing for easy decomposition post-deposition, with a need for stable and adaptable metal precursors that meet specific application requirements.

Innovation Solution

A process using a compound of general formula (I) where the ligand L is tridentate, bound to the metal M via phosphor and nitrogen atoms, allowing for controlled deposition and subsequent decomposition, with the ability to modify the precursor's properties to fit specific needs, using a combination of gaseous or aerosol state deposition and self-limiting processes like ALD.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If volatile precursors with ligands are used to deposit metal atoms at moderate temperatures, then deposition at moderate temperatures is achieved, but ligand removal and decomposition are required after deposition

Engineering Contradiction:
Improvedeposition temperatureVSAvoidpost-deposition processing complexity
Core Design Contradiction:
TemperatureVSEase of manufacture

Solution Approach 1:

The patent extracts and removes the ligand component from the precursor molecule before deposition occurs. By using precursors that release their ligands during the deposition process itself, the harmful ligand removal step is integrated into the deposition process, eliminating separate post-deposition ligand removal operations.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent performs preliminary decomposition of the precursor to generate reactive metal species before they reach the substrate. The precursor is designed to decompose in advance during transport, releasing the metal atom or cluster that then deposits on the substrate without requiring subsequent ligand removal.

Inventive Principle:
Principle #10Preliminary action

2Stability of the object's composition

If precursor decomposition is minimized before substrate contact, then precursor stability is improved, but controlled decomposition on substrate is required

Engineering Contradiction:
Improveprecursor stabilityVSAvoidfilm quality
Core Design Contradiction:
Stability of the object's compositionVSManufacturing precision

Solution Approach 1:

The patent creates different stability conditions in different locations: the precursor remains stable during transport and storage (bulk stability) but decomposes readily when it contacts the substrate surface (local reactivity). This is achieved by designing precursors with labile bonds that break upon substrate interaction, ensuring film quality while maintaining precursor stability.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The substrate acts as an intermediary that triggers precursor decomposition. The precursor is designed to be stable in the gas phase but to decompose when interacting with the substrate surface, using the substrate itself as the catalyst or trigger for the decomposition reaction.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If tridentate ligands occupying three coordination sites are used, then precursor stability and controlled decomposition are improved, but precursor complexity increases

Engineering Contradiction:
Improvedeposition reproducibilityVSAvoidprecursor molecular complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges multiple functions into the single tridentate ligand molecule: it provides stability to the metal center during handling, controls the decomposition pathway, and influences the deposition morphology. By combining these functions into one integrated ligand structure, the overall system complexity is reduced despite the ligand's complexity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent uses composite precursor molecules consisting of metal centers coordinated with tridentate ligands. These composite structures combine the stability of the metal-ligand coordination sphere with the controlled decomposition properties, achieving reliable and reproducible deposition through the synergistic combination of components.

Inventive Principle:
Principle #40Composite materials

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 enables the production of high-quality, reproducible inorganic films with minimal precursor decomposition, achieving uniform and conformal films suitable for electronic elements and fine structures, with the ability to vary process parameters for different applications.

Implementation Method 1

a compound of general formula (I) is brought into the gaseous or aerosol state

Methodology Applied
Scientific EffectVaporization: Evaporation

Implementation Method 2

a compound of general formula (I) is deposited on a solid substrate from the gaseous or aerosol state

Methodology Applied
Scientific EffectPhysical vapor deposition: Physical Vapour Deposition

Implementation Method 3

the deposited compound of general formula (I) is decomposed by heating the solid substrate to a temperature between 50°C and 300°C

Methodology Applied
Scientific EffectThermal decomposition: Pyrolysis

Data Source

PatentEP3177751B1Process for the generation of thin inorganic films
Publication Date: 2020.10.07 BASF SE
  • EP3177751B1 patent drawingFigure 1~2
  • EP3177751B1 patent drawingFigure 3~4
  • EP3177751B1 patent drawingFigure 5~6

AI summary

The present invention is in the field of processes for the generation of thin inorganic films on substrates. More specifically, the present invention relates to a process comprising bringing a compound of general formula (I) into the gaseous or aerosol state and depositing the compound of general formula (I) from the gaseous or aerosol state onto a solid substrate, wherein R11, R12, R13, R14, R15, R16, R17, R18 are independent of each other hydrogen, an alkyl group, an aryl group, or a trialkylsilyl group, R21, R22, R23, R24 are independent of each other an alkyl group, an aryl group, or a trialkylsilyl group, n is 1 or 2, M is a metal or semimetal, X is a ligand which coordinates M, and m is an integer from 0 to 3.