Master Oscillator Grating Attitude Control for Laser Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Chromatic aberration in gas laser apparatuses used for semiconductor exposure leads to reduced resolution due to wide natural oscillation amplitude, necessitating narrower spectral bandwidths, which existing technologies struggle to achieve effectively.
Innovation Solution
A master oscillator system with a grating as a resonator mirror, an optical element like a prism, and an attitude control mechanism to adjust the prism's tilt, ensuring the laser beam's spectral bandwidth is narrowed to minimize chromatic aberration, integrated with an amplifying apparatus to stabilize laser oscillation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the natural oscillation amplitude of the gas laser apparatus is used, then the laser beam can be emitted with high intensity, but chromatic aberration occurs leading to reduced resolution
Solution Approach 1:
The patent divides the laser system into a master oscillator section and an amplifier section. The master oscillator generates laser light with narrow spectral bandwidth (high precision), while the amplifier section boosts the intensity. This segmentation allows both high resolution and high intensity to be achieved separately and combined.
Solution Approach 2:
The patent introduces dynamic adjustment mechanisms including an attitude control mechanism for the optical element and a beam width adjustment mechanism. These dynamic controls allow real-time optimization of the laser beam parameters to maintain both narrow spectral bandwidth and high intensity under varying operating conditions.
2Manufacturing precision
If a line narrow module is provided to narrow the spectral bandwidth, then chromatic aberration is reduced, but the device complexity increases
Solution Approach 1:
The patent combines the line-narrowing function directly into the resonator structure of the master oscillator by using a grating as one of the resonator mirrors. This integration eliminates the need for separate line narrow modules, reducing device complexity while maintaining spectral bandwidth control.
Solution Approach 2:
The grating in the resonator serves multiple functions: it acts as a resonator mirror for laser oscillation and simultaneously provides spectral selection for line narrowing. The optical element also serves both beam width control and spectral bandwidth control functions, reducing the need for separate dedicated components.
3Manufacturing precision
If the spectral bandwidth is narrowed to reduce chromatic aberration, then resolution is improved, but the laser oscillation stability becomes difficult to maintain
Solution Approach 1:
The patent employs feedback control mechanisms including an attitude control mechanism that adjusts the optical element's position based on detected beam parameters, and a beam width adjustment mechanism with feedback control. These feedback systems continuously monitor and adjust the laser parameters to maintain both narrow spectral bandwidth and stable oscillation.
Solution Approach 2:
The patent introduces dynamic adjustment mechanisms that can adapt in real-time to maintain laser oscillation stability. The attitude control mechanism and beam width adjustment mechanism dynamically optimize the laser parameters, allowing the system to maintain stable oscillation even with narrow spectral bandwidth under varying operating conditions.
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 system achieves stable and precise control over the spectral bandwidth, reducing chromatic aberration and enhancing the resolution of semiconductor exposure devices by effectively narrowing the laser beam's spectral width.
Implementation Method 1
a grating that functions as one of a plurality of resonator mirrors in an optical resonator
Implementation Method 2
the optical element is a prism. In addition, the attitude control mechanism may adjust the attitude of the prism so that an axis at which two surfaces including two entry/exit surfaces, respectively, of the laser light in the prism intersect is tilted
Data Source
AI summary
A master oscillator system may include a grating that functions as one of a plurality of resonator mirrors in an optical resonator, an optical element disposed within an optical path between the plurality of resonator mirrors, and an attitude control mechanism that adjusts an angle at which laser light traveling within the optical resonator is incident on the grating by adjusting the attitude of the optical element.