Silicon Carbide Powder Nitrogen Doping for Single Crystal Growth

Solution Overview

Problem

The challenge in fabricating n-type silicon carbide single crystals is the inefficient and costly process of uniformly supplying nitrogen gas during high-temperature growth, which complicates the doping process and increases costs.

Innovation Solution

Manufacturing silicon carbide powder with a nitrogen concentration range of 100 ppm to 5000 ppm by mixing silicon and carbon sources, heating, and introducing a nitrogen-based gas during the process, allowing the powder to serve as a raw material for growing silicon carbide single crystals without additional nitrogen gas supply.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If nitrogen gas is supplied during the single crystal growing process to fabricate n-type silicon carbide, then doping concentration can be achieved, but uniformity of nitrogen supply deteriorates and process complexity increases

Engineering Contradiction:

Improvedoping concentrationVSAvoiddoping uniformity

Core Design Contradiction:

Quantity of substanceVSManufacturing precision

Solution Approach 1:

Nitrogen is incorporated into the silicon carbide powder during the powder fabrication process before the single crystal growth. This preliminary doping of the raw material ensures that nitrogen is already present in the material at the desired concentration levels, eliminating the need for complex nitrogen gas supply systems during crystal growth and ensuring uniform distribution throughout the crystal structure

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The doping function is merged with the raw material preparation process. Instead of separating powder fabrication and doping into distinct steps, the invention combines nitrogen incorporation into the silicon carbide powder synthesis, integrating two processes into one and simplifying the overall manufacturing workflow

Inventive Principle:

Principle #5Merging (Combining)

2Quantity of substance

If nitrogen gas is supplied during the single crystal growing process, then doping can be achieved, but process cost increases

Engineering Contradiction:

Improvedoping concentrationVSAvoidprocess cost

Core Design Contradiction:

Quantity of substanceVSEase of manufacture

Solution Approach 1:

Nitrogen is incorporated into the silicon carbide powder during the powder fabrication process before the single crystal growth. This preliminary doping of the raw material ensures that nitrogen is already present in the material at the desired concentration levels, eliminating the need for complex nitrogen gas supply systems during crystal growth and ensuring uniform distribution throughout the crystal structure

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The nitrogen supply function is extracted from the crystal growth process and transferred to the powder fabrication process. By removing the need for nitrogen gas supply equipment and operations during crystal growth, the invention simplifies the manufacturing system and reduces associated costs

Inventive Principle:

Principle #2Taking out (Extraction)

3Quantity of substance

If nitrogen gas is supplied during the single crystal growing process, then doping can be achieved, but process efficiency deteriorates

Engineering Contradiction:

Improvedoping concentrationVSAvoidprocess efficiency

Core Design Contradiction:

Quantity of substanceVSProductivity

Solution Approach 1:

Nitrogen is incorporated into the silicon carbide powder during the powder fabrication process before the single crystal growth. This preliminary doping of the raw material ensures that nitrogen is already present in the material at the desired concentration levels, eliminating the need for complex nitrogen gas supply systems during crystal growth and ensuring uniform distribution throughout the crystal structure

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The doping function is merged with the raw material preparation process. Instead of separating powder fabrication and doping into distinct steps, the invention combines nitrogen incorporation into the silicon carbide powder synthesis, integrating two processes into one and simplifying the overall manufacturing workflow

Inventive Principle:

Principle #5Merging (Combining)

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 method reduces process costs and improves efficiency by ensuring uniform nitrogen doping in the silicon carbide single crystals, enabling high-quality crystal growth without the need for separate nitrogen gas supply during the crystal growth process.

Implementation Method 1

supplying a nitrogen-based gas into the mixture

Methodology Applied

Scientific EffectAbsorption: Absorption (physical)

Implementation Method 2

growing a silicon carbide single crystal on a seed fixed by a holder placed at an upper portion of the crucible by sublimating the raw material

Methodology Applied

Scientific EffectSublimation: Sublimation

Data Source

PatentUS9920450B2Silicon carbide powder, method for manufacturing the same and method for growing single crystal

Publication Date: 2018.03.20 S TECH CO LTD

AI summary

A silicon carbide powder according to the embodiment includes nitrogen having a concentration in a range of about 100 ppm to about 5000 ppm. A method for manufacturing silicon carbide powder according to the embodiment includes preparing a mixture by mixing a silicon source including silicon with a solid carbon source or a carbon source including an organic carbon compound; heating the mixture; cooling the mixture; and supplying a nitrogen-based gas into the mixture.