SiC Substrate Micro Patterns for Epitaxial Growth

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing methods for growing semiconductor crystals on silicon carbide substrates are complicated and costly due to the need for buffer layers to reduce basal plane dislocation (BPD), which deteriorate the substrate surface and increase manufacturing time.

Innovation Solution

Forming micro patterns or grooves on the silicon carbide substrate using an atomic force microscope (AFM) to prevent BPD, allowing for the direct growth of an epitaxial layer without the need for a buffer layer, thereby reducing manufacturing costs and improving substrate quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a buffer layer is formed to reduce BPD, then the reliability of the semiconductor device is improved, but the manufacturing process becomes complicated and the manufacturing cost increases

Engineering Contradiction:
Improvedevice reliabilityVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts and removes the buffer layer from the manufacturing process. By forming patterns directly on the silicon carbide substrate, the patent eliminates the need for the buffer layer while still achieving BPD reduction, thereby simplifying the manufacturing process and reducing costs while maintaining device reliability

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention performs preliminary action by forming patterns on the substrate before epitaxial growth. These pre-formed patterns serve to control and reduce BPD during the subsequent epitaxial layer formation, replacing the traditional buffer layer approach with a more efficient preliminary structuring step

Inventive Principle:
Principle #10Preliminary action

2Reliability

If a buffer layer is formed to reduce BPD, then the reliability of the semiconductor device is improved, but the manufacturing time is increased

Engineering Contradiction:
Improvedevice reliabilityVSAvoidmanufacturing time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The buffer layer formation steps including mask formation, pattern formation through etching, and regrowing are completely removed from the process. The patent achieves BPD reduction through direct pattern formation on the substrate, eliminating the time-consuming multi-step buffer layer process while maintaining reliability

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention skips the intermediate buffer layer formation steps entirely. By directly forming patterns on the silicon carbide substrate and proceeding to epitaxial growth, the patent rushes through the traditional lengthy process while still achieving the desired BPD reduction for reliable devices

Inventive Principle:
Principle #21Skipping (Rushing through)

3Reliability

If a buffer layer is formed to reduce BPD, then the reliability of the semiconductor device is improved, but the quality of the substrate surface is deteriorated

Engineering Contradiction:
Improvedevice reliabilityVSAvoidsubstrate surface quality
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The buffer layer and its associated processing steps are removed, eliminating the sources of surface damage. The patent forms patterns directly on the substrate and proceeds to epitaxial growth, avoiding the mask formation, etching, and regrowing processes that deteriorate substrate surface quality while still achieving BPD reduction

Inventive Principle:
Principle #2Taking out (Extraction)

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 significantly reduces BPD by 50% or more, enabling the growth of high-quality epitaxial layers with reduced manufacturing costs and time, while maintaining the reliability and crystallinity of the semiconductor layer.

Implementation Method 1

the micro patterns are formed by using the atomic force microscope (AFM) or grooves are formed on the base substrate by removing an oxide layer pattern, which is formed by using the AFM

Methodology Applied
Scientific EffectAtomic force microscope (AFM): Scanning Probe Microscopy

Implementation Method 2

forming an epitaxial layer on the silicon carbide substrate

Methodology Applied
Scientific EffectEpitaxy: Epitaxy

Data Source

PatentEP2724362B1Semiconductor device and method for growing semiconductor crystal
Publication Date: 2020.02.12 LG INNOTEK CO LTD
  • EP2724362B1 patent drawingFigure 1~4
  • EP2724362B1 patent drawingFigure 5~9
  • EP2724362B1 patent drawingFigure 10~12

AI summary

A semiconductor device according to the embodiment comprises a base substrate; patterns on the base substrate; and an epitaxial layer on the base substrate, wherein the epitaxial layer is formed on a surface of the substrate exposed among the patterns. A method for growing a semiconductor crystal comprises the steps of cleaning a silicon carbide substrate; forming patterns on the silicon carbide substrate; and forming an epitaxial layer on the silicon carbide substrate.