Remote Plasma SiC Film Deposition for Step Coverage Without Metal Oxidation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current plasma-enhanced chemical vapor deposition (PECVD) processes face challenges in depositing high-quality silicon carbide thin films with excellent step coverage, low dielectric constants, high breakdown voltages, low leakage currents, and porosity, while avoiding oxidation of exposed metal surfaces.

Innovation Solution

A method involving the deposition of silicon carbide films using a remote plasma source, where silicon-containing precursors with Si—H bonds are combined with hydrocarbon co-reactants, and hydrogen radicals generated in a remote plasma source are introduced to react with the precursors, forming doped or undoped silicon carbide films without C—C bonds or substantially no C—N bonds.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If traditional PECVD processes are used to deposit silicon carbide films, then deposition can be achieved, but the films exhibit poor step coverage, high dielectric constants, and oxidation of metal surfaces

Engineering Contradiction:

Improvestep coverageVSAvoidoxidation of metal surfaces

Core Design Contradiction:

Manufacturing precisionVSObject-generated harmful factors

Solution Approach 1:

The process is segmented into two distinct zones: a remote plasma generation zone upstream and a deposition zone downstream. The plasma is generated remotely using hydrogen source gas that does not contact the substrate directly, while precursors are introduced separately in the deposition zone. This spatial segmentation prevents oxidative species from reaching metal surfaces while maintaining effective silicon carbide deposition

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Hydrogen radicals generated in the remote plasma act as an intermediary species that reacts with silicon-containing precursors to form silicon carbide films. The hydrogen radicals serve as a controlled reactive intermediate that enables film formation without introducing oxidative harmful effects to metal surfaces

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If conventional PECVD is used, then deposition occurs, but films have high dielectric constants and poor electrical properties

Engineering Contradiction:

Improveelectrical propertiesVSAvoidprocess complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The process changes key parameters by using hydrogen radicals in specific concentration ranges (0.1-10% of total gas flow) and controlling the distance between plasma generation and deposition zones. These parameter changes enable formation of films with low dielectric constants and high breakdown voltages while maintaining process controllability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The conventional direct plasma exposure mechanism is replaced with a remote plasma field mechanism. Instead of using reactive plasma species that directly contact and damage substrates, the invention uses a remote plasma field to generate hydrogen radicals that diffuse to the substrate, reducing direct mechanical and chemical damage while improving film quality

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Productivity

If plasma is generated close to the substrate, then deposition efficiency increases, but metal surfaces are oxidized and film quality deteriorates

Engineering Contradiction:

Improvedeposition efficiencyVSAvoidoxidation damage

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The invention transitions from a two-dimensional direct plasma-substrate interaction to a three-dimensional remote plasma field configuration. Plasma is generated in a volume upstream, and hydrogen radicals diffuse through the gas phase to reach the substrate, adding a spatial dimension that separates plasma generation from film deposition while maintaining efficiency

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

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 achieves high-quality silicon carbide films with improved step coverage, electrical properties, and porosity, while preventing oxidation of metal surfaces, thereby addressing the limitations of traditional PECVD methods.

Implementation Method 1

generating, from a hydrogen source gas, radicals of hydrogen in a remote plasma source

Methodology Applied

Scientific EffectPlasma: Plasma

Implementation Method 2

depositing a silicon carbide film on a substrate... flowing a silicon-containing precursor into the reaction chamber... flowing a co-reactant into the reaction chamber

Methodology Applied

Scientific EffectChemical Vapour Deposition: Chemical Vapour Deposition

Data Source

PatentUS20250149328A1Remote plasma based deposition of silicon carbide films using silicon-containing and carbon-containing precursors

Publication Date: 2025.05.08 LAM RES CORP

AI summary

A doped or undoped silicon carbide film can be deposited using a remote plasma chemical vapor deposition (CVD) technique. One or more silicon-containing precursors are provided to a reaction chamber. Radical species, such as hydrogen radical species, are provided in a substantially low energy state or ground state and interact with the one or more silicon-containing precursors to deposit the silicon carbide film. A co-reactant may be flowed with the one or more silicon-containing precursors, where the co-reactant is a carbon-containing precursor and each silicon-containing precursor is a silane-based precursor with at least a silicon atom having two or more hydrogen atoms bonded to the silicon atom.