Rapid Thermal Treatment for Semiconductor Epitaxial Contaminant Removal

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional methods face challenges in forming high-quality epitaxial silicon germanium materials for strained MOS devices as device sizes decrease, due to limitations in existing epitaxial structures and processes.

Innovation Solution

A method involving a semiconductor substrate with contaminants, including a carbon species, is treated using a wet processing technique to remove the oxide layer and subjected to high energy electromagnetic radiation to increase the surface temperature above 1000 degrees Celsius for a short duration, followed by rapid cooling, to effectively remove contaminants and facilitate epitaxial material growth.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional epitaxial structures and processes are used to form silicon germanium materials, then the process is compatible with existing technology, but the quality of epitaxial materials deteriorates as device sizes decrease

Engineering Contradiction:

Improvequality of epitaxial silicon germanium materialsVSAvoidadaptability to decreasing device sizes

Core Design Contradiction:

Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The patent applies parameter changes by modifying the thermal parameters of the epitaxial process through rapid thermal annealing. By controlling the temperature profile (heating rate, peak temperature, and cooling rate) rather than changing the fundamental epitaxial process, the method achieves high-quality silicon germanium formation at scaled device dimensions while remaining compatible with existing technology

Inventive Principle:

Principle #35Parameter changes

2Manufacturing precision

If conventional thermal processing is used for extended periods, then contaminants can be removed, but the thermal budget increases affecting device performance

Engineering Contradiction:

Improvecontaminant removal effectivenessVSAvoidthermal budget

Core Design Contradiction:

Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The patent implements periodic action through rapid thermal annealing with controlled heating and cooling cycles. The surface is heated rapidly to high temperature for a short duration (removing contaminants) then quickly cooled, creating a periodic thermal action that achieves contaminant removal with minimal thermal budget accumulation

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The method applies the principle of rushing through the thermal processing step by using very rapid heating and cooling rates. The high temperature exposure is minimized to only the time necessary for contaminant removal, skipping through the thermal budget that would otherwise accumulate in conventional slow thermal processing

Inventive Principle:

Principle #21Skipping (Rushing through)

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 enhances device yields, reduces thermal budget, and is compatible with conventional technology, providing a rapid thermal treatment process that improves the formation of strained silicon MOS devices without substantial equipment modifications.

Implementation Method 1

subjecting the surface region to a high energy electromagnetic radiation having wavelengths ranging from about 300 to about 800 nanometers for a time period of less than 1 second to increase a temperature of the surface region to greater than 1000 degrees Celsius to remove the one or more contaminants

Methodology Applied

Scientific EffectElectromagnetic radiation heating: Dielectric Heating

Implementation Method 2

removing the high energy electromagnetic radiation to cause a reduction in temperature to about 300 degrees Celsius to about 600 degrees Celsius in a time period of less than 1 second

Methodology Applied

Scientific EffectRapid cooling: Adiabatic Cooling

Data Source

PatentUS8309472B2Method of rapid thermal treatment using high energy electromagnetic radiation of a semiconductor substrate for formation of epitaxial materials

Publication Date: 2012.11.13 SEMICON MFG INT (SHANGHAI) CORP

AI summary

A method for fabricating semiconductor devices includes providing a semiconductor substrate having a surface region containing one or more contaminants and having an overlying oxide layer. In an embodiment, the one or more contaminants are at least a carbon species. The method includes processing the surface region using at least a wet processing process to selectively remove the overlying oxide layer and expose the surface region including the one or more contaminants. The method includes subjecting the surface region to a high energy electromagnetic radiation having wavelengths ranging from about 300 to about 800 nanometers for a time period of less than 1 second to increase a temperature of the surface region to greater than 1000 degrees Celsius to remove the one or more contaminants. The method includes removing the high energy electromagnetic radiation to cause a reduction in temperature to about 300 to about 600 degrees Celsius in a time period of less than 1 second.