Homogenizer Shielding Apparatus for Semiconductor Optical Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The airflow generated by fans in semiconductor device fabrication tools causes contamination from dust and particles to accumulate on the homogenizer, leading to blemishes in wafer/substrate images.
Innovation Solution
A shielding apparatus is positioned between the exit/entrance portion of the homogenizer and the optical outlet, using a shielding element and mounting element to divert airflow and trap contaminants, preventing them from reaching the imaging plane.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If fans are used to regulate lamp heating in the lamphouse, then temperature control is improved, but airflow causes dust and particles to accumulate on the homogenizer
Solution Approach 1:
A shielding element is introduced as an intermediary component between the homogenizer and the contaminated airflow path. This shield intercepts dust-laden air currents generated by the cooling fans, preventing particles from reaching and accumulating on the homogenizer surface while allowing the fans to continue their temperature regulation function
Solution Approach 2:
The harmful airflow path carrying dust and particles is separated from the homogenizer by removing the direct exposure. The shielding element extracts the contaminant-laden air stream from reaching the homogenizer, directing it away while maintaining the necessary cooling airflow for the lamp
2Illumination intensity
If the homogenizer is exposed to the optical path, then optical transmission is maintained, but contamination from airflow causes blemishes in wafer images
Solution Approach 1:
The shielding element is designed with selective properties: it is positioned and shaped to block contaminant particles locally at the homogenizer surface, while maintaining optical transmission in the necessary paths. The shield's geometry allows light to pass through designated areas while intercepting dust-laden airflow in other zones
Solution Approach 2:
The shielding element serves as a mediator between the optical path requirements and the contamination prevention needs. It allows optical transmission where required while blocking particle-laden airflow, thus protecting image quality without compromising optical functionality
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
Effectively prevents contamination from reaching the imaging plane, reducing blemishes in images by diverting airflow and trapping particles, thus improving the quality of wafer/substrate inspections.
Implementation Method 1
the one or more fans may act to 'suck' air out of the top portion of the lamphouse assembly into the lower portion of the lamphouse assembly occupied, in part, by a homogenizer
Implementation Method 2
the shielding element being positioned between the exit portion of the homogenizer and an optical outlet of the optical system
Data Source
AI summary
A shielding apparatus for protecting a homogenizer in a broadband optical system includes a shielding element and a mounting element configured to secure the shielding element at a position at least proximate to an exit portion of a homogenizer of an optical system, the shielding element being positioned between the exit portion of the homogenizer and an optical outlet of the optical system.