Variable-Section Susceptor Chamber for Uniform Epitaxial Heating
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Solution Overview
Problem
Existing reaction chambers for epitaxial deposition fail to achieve uniform temperature distribution across substrates, leading to non-uniform heating and difficulty in direct temperature measurement during deposition processes.
Innovation Solution
The susceptor assembly in the reaction chamber is designed with varying cross-sections and thicknesses along its longitudinal and transverse positions to control heat generation, using electromagnetic induction to create non-uniform heating profiles that match desired temperature profiles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If a susceptor assembly with uniform cross-section is used, then the structure is simple and easy to manufacture, but the temperature distribution across substrates becomes non-uniform
Solution Approach 1:
The susceptor assembly is designed with non-uniform cross-sectional dimensions along its longitudinal axis, creating different heating characteristics in different zones. The first susceptor element has varying thickness or width at different positions to generate different heat quantities in end zones versus intermediate zones, achieving local temperature optimization for uniform substrate heating.
Solution Approach 2:
The geometric parameters of the susceptor assembly (cross-sectional dimensions, thickness) are deliberately varied along the longitudinal direction to change the electromagnetic induction heating characteristics. This parameter variation allows different zones to generate appropriate heat quantities, transforming the uniform heating problem into a controlled non-uniform heating pattern that results in uniform substrate temperature.
2Measurement precision
If direct temperature measurement is attempted during deposition, then real-time temperature data can be obtained, but the measurement process interferes with the deposition and is technically difficult
Solution Approach 1:
Instead of directly measuring substrate temperature during deposition, the patent uses the susceptor assembly as an intermediary element. By measuring and controlling the susceptor's temperature and heating characteristics, the system indirectly controls and monitors the substrate temperature without direct contact or interference with the deposition process.
Solution Approach 2:
The susceptor assembly serves dual functions: it generates heat for substrate heating and simultaneously acts as a temperature reference and control element. The system uses the susceptor's own heating characteristics and temperature response to infer and control substrate temperature, eliminating the need for separate measurement systems that would interfere with deposition.
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 design achieves more uniform temperature distribution across substrates, improving deposition processes by reducing temperature non-uniformity and enabling effective indirect temperature measurement.
Implementation Method 1
an inductor 9 is wrapped, being adapted to heat by electromagnetic induction the elements 2, 3, 4 and 5 which are made of graphite
Implementation Method 2
the inductor 9 is supplied with an alternating current, alternating electrical currents are induced in the susceptor elements 2, 3, 4 and 5... These currents create heat by the Joule effect
Data Source
AI summary
The reaction chamber (100A) is used for a reactor for the deposition of semiconductor material on a substrate (62); it extends in a longitudinal direction and comprises a reaction and deposition zone (10) which extends in the longitudinal direction; this zone (10) is defined by susceptor elements (21A, 21B, 21C, 22A, 22B, 31, 32) adapted to be heated by electromagnetic induction; a first susceptor element (21A, 21B, 21C, 22A, 22B) is opposite to a substrate support element (61) of the chamber and has a hole (20) which extends in the longitudinal direction along its whole length; the first susceptor element (21A. 21B, 21C, 22A, 22B) has a non-uniform cross section that depends on its longitudinal position.