Multi-Point Semiconductor Wafer Temperature Measurement Using Interference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current temperature measurement methods for semiconductor wafers require multiple apparatuses and lengthy processes to measure temperatures at multiple points, increasing labor and cost while being inefficient.
Innovation Solution
A temperature measuring apparatus with a light source, first and second splitters, and optical path length altering means to radiate measurement beams with varying optical path lengths onto multiple points, allowing simultaneous interference measurement and temperature calculation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple temperature measuring apparatuses are used to measure temperatures at multiple points, then measurement coverage is improved, but device complexity and cost increase
Solution Approach 1:
The patent combines multiple temperature measurement functions into a single apparatus by using one light source and one light receiver that can detect interference waves from multiple measurement points simultaneously. The single apparatus measures temperatures at multiple points by receiving reflected light from different locations on the work substrate, thereby eliminating the need for multiple separate apparatuses while maintaining comprehensive temperature measurement coverage.
Solution Approach 2:
The light receiver is designed to perform multiple functions by detecting interference waves from multiple measurement points simultaneously. A single light receiver can measure temperatures at different locations on the work substrate without requiring separate receivers for each point, making the apparatus universal and multi-functional in terms of temperature measurement capability.
2Measurement precision
If multiple temperature measuring apparatuses are used to measure temperatures at multiple points, then measurement coverage is improved, but labor and time requirements increase
Solution Approach 1:
The patent combines multiple temperature measurement operations into a single simultaneous process. The single apparatus with one light receiver measures temperatures at multiple points at the same time rather than sequentially, dramatically reducing the total measurement time and eliminating the labor involved in operating multiple separate apparatuses.
3Measurement precision
If optical path length is altered to enable depthwise temperature measurement, then measurement capability is improved, but device complexity increases
Solution Approach 1:
The patent uses periodic oscillation of the reference mirror to alter the optical path length of the reference beam. By moving the reference mirror back and forth in a periodic manner, the system can measure temperatures at different depths within the work substrate without requiring complex mechanical adjustment mechanisms, thereby achieving depthwise measurement capability with relatively simple device structure.
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
Enables accurate, simultaneous temperature measurement at multiple points on semiconductor wafers, reducing labor and cost while improving measurement efficiency.
Implementation Method 1
both reflected light beams reenter the beam splitter 14, and depending upon the optical path length of the reference beam, the reflected light beams become superimposed upon each other, thereby inducing interference
Implementation Method 2
the measurement beam is radiated toward the temperature measurement target and is reflected at various layers, whereas the reference beam is radiated toward the reference mirror 20 and is reflected at the mirror surface
Data Source
AI summary
Light from a light source is split at a first splitter into a temperature measurement beam and a reference beam, the temperature measurement beam is further split at a second splitter into first through nth measurement beams, and the reference beam is reflected at a reference beam reflecting means. The first through nth measurement beams are radiated onto a temperature measurement target by ensuring that the optical path lengths of the first through nth measurement beams extending from the second splitter to the temperature measurement target are different from one another. By driving the reference beam reflecting means, the optical path length of the reference beam reflected at the reference beam reflecting means is altered, and concurrently, a light receiving means senses and measures interference induced by the first through and measurement beams reflected at the temperature measurement target and the reference beam reflected at the reference beam reflecting means.