Light Pipe Arrays for Uniform Thermal Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lampheads in thermal processing chambers for semiconductor substrates exhibit irregular irradiance patterns, leading to non-uniform heating due to manufacturing variations, which complicates the thermal processing of shrinking semiconductor device features.
Innovation Solution
A light pipe array comprising transparent, non-metallic structures with longitudinal axes positioned orthogonally to the chamber wall, coupled with a radiant heat source, to improve radiance control and distribute heat uniformly across the substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional lampheads with multiple light sources are used to heat the substrate, then thermal processing capability is achieved, but irregular irradiance patterns result in non-uniform heating
Solution Approach 1:
Light pipes serve as intermediary optical elements between the lampheads and the substrate. The light pipes transmit and redistribute the radiant energy from multiple light sources, transforming the irregular irradiance pattern into a uniform distribution across the substrate surface, thereby achieving both thermal processing capability and heating uniformity
Solution Approach 2:
The patent changes the optical parameters of the system by introducing light pipes with specific refractive indices, lengths, and diameters. These parameter modifications enable the light pipes to effectively redistribute the light energy, converting the irregular irradiance pattern from conventional lampheads into a uniform heating pattern on the substrate
2Manufacturing precision
If lamp heating is used for thermal processing, then processing capability is maintained, but irradiance control precision deteriorates due to manufacturing variations
Solution Approach 1:
The light pipes act as optical mediators that decouple the irradiance control function from the lamphead manufacturing variations. By transmitting light through the light pipes, the system achieves precise irradiance control at the substrate level, independent of the lamphead manufacturing tolerances
Solution Approach 2:
The patent segments the optical path into multiple light pipes, each contributing to the overall irradiance distribution. This segmentation allows for better control and optimization of the light distribution pattern, improving the precision of thermal processing despite variations in individual light source manufacturing
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
The light pipe array enhances radiance distribution, resulting in a smoother and more uniform irradiance pattern on the substrate, reducing thermal processing variability and improving the precision of semiconductor manufacturing.
Implementation Method 1
each of the plurality of light pipe structures comprising a transparent material... in optical communication with a respective energy source
Data Source
AI summary
A processing chamber is described. The processing chamber includes a chamber having an interior volume, a light pipe array coupled to the chamber, the light pipe array comprising a wall member that defines a boundary of the interior volume of the chamber, wherein the light pipe array includes a plurality of non-metallic light pipe structures, and a radiant heat source comprising a plurality of energy sources in optical communication with each of the plurality of light pipe structures.