Susceptor Ring Modulates Temperature Profile for Epitaxial CVD Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Epitaxial chemical vapor deposition (CVD) growth rates are not uniform across semiconductor wafers due to local temperature deviations and flow velocity issues, leading to degradation in wafer flatness.
Innovation Solution
A susceptor assembly with a ring positioned below the susceptor to adjust the radial thickness profile of the deposited layer, using a transparent or translucent ring to modulate the temperature profile and correct non-uniformities by increasing or decreasing material deposition at specific regions of the wafer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional susceptor is used for supporting wafers during epitaxial CVD, then the deposition process can be performed, but the growth rates are not uniform across the wafer surface due to local temperature deviations
Solution Approach 1:
The patent applies local quality by positioning a transparent ring at specific radial locations below the susceptor to create localized temperature modifications. The ring is strategically placed to address specific temperature deviations in different regions of the wafer, allowing each area to receive customized thermal treatment for uniform growth rates
Solution Approach 2:
The transparent ring acts as an intermediary element between the heat source and the susceptor. It modulates the thermal field by transmitting and distributing heat uniformly across the susceptor, thereby correcting local temperature deviations without directly contacting the susceptor or wafer
2Manufacturing precision
If the susceptor is rotated during deposition to improve uniformity, then growth evenness can be enhanced, but the complexity of the apparatus increases
Solution Approach 1:
The patent applies self-service by using the natural rotation of the susceptor during the deposition process to achieve uniformity. The system leverages the inherent rotational movement already present in the deposition apparatus, eliminating the need for additional complex rotation control mechanisms while still achieving even growth distribution
3Manufacturing precision
If a ring is positioned below the susceptor to correct thickness non-uniformity, then the radial deposition profile uniformity is improved, but the device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the thermal correction function into discrete transparent ring elements positioned at specific radial locations. Rather than using a continuous complex heating system, the ring is segmented into strategic positions that address specific thickness non-uniformities, simplifying the overall device structure while achieving precise control
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
Improves the uniformity of epitaxial CVD growth rates, enhances production efficiency, and reduces waste by ensuring a more uniform radial deposition profile, thereby improving wafer quality and lowering operational costs.
Implementation Method 1
using a transparent or translucent ring to modulate the temperature profile
Implementation Method 2
A ring is disposed below the susceptor at a radial location that corresponds to the thickness non-uniformity in the thickness profile to increase or decrease the thickness of the layer
Implementation Method 3
Epitaxial chemical vapor deposition (CVD) is a process for growing a thin layer of material on a semiconductor wafer
Implementation Method 4
introducing a vaporous silicon source gas, such as silane or a chlorinated silane, to the front surface of the wafer to deposit and grow an epitaxial layer of silicon
Data Source
AI summary
Apparatus and methods for wafer processes such as etching and chemical vapor deposition processes are disclosed. In some embodiments, the apparatus includes a susceptor and a ring disposed beneath the susceptor to influence a thickness of the deposited epitaxial layer.