Line Narrowing Module Mirror Mount for Stable Spectral Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas laser devices used in semiconductor exposure face challenges with chromatic aberration due to wide spectral linewidths of KrF and ArF excimer laser beams, leading to decreased resolution, which necessitates a line narrowing module to reduce spectral linewidth and mitigate aberration effects.
Innovation Solution
A line narrowing module incorporating a prism, mirror, grating, holding part, adhesives, and a driving unit that rotates the mirror to adjust the light's wavelength dispersion, ensuring the second adhesive is positioned opposite the first adhesive relative to the mirror's center, enhancing the module's stability and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a line narrowing module is added to narrow the spectral linewidth, then chromatic aberration is reduced and resolution is improved, but the device complexity increases
Solution Approach 1:
The patent combines multiple optical elements (prism, grating, mirror) into a single integrated line narrowing module. The prism and grating are positioned to work together in sequence within a compact housing, and the mirror is integrated with the holding part that can rotate to adjust the optical path. This merging of functions reduces the overall system complexity compared to having separate components while still achieving the desired spectral linewidth narrowing to improve resolution.
Solution Approach 2:
The holding part serves multiple functions: it holds the mirror in position, provides a rotation axis for adjusting the mirror angle, and acts as part of the optical path structure. The driving unit that rotates the holding part not only adjusts the mirror angle for wavelength selection but also enables the module to adapt to different operating conditions. This multi-functionality reduces the number of separate components needed, thereby reducing device complexity while maintaining the ability to narrow spectral linewidth for high resolution.
2Reliability
If multiple adhesives are used to bond the mirror to the holding part, then the reliability and stability of the mirror positioning is improved, but the manufacturing process becomes more complex
Solution Approach 1:
The patent applies adhesives at specific locations on the mirror surface rather than uniformly across the entire surface. The first adhesive is applied between the holding part and a first adjacent surface or opposing surface of the mirror, while the second adhesive is applied between the holding part and a second adjacent surface. This localized application ensures that critical bonding points are strengthened for reliable mirror positioning, while avoiding unnecessary adhesive application that would complicate manufacturing. The selective placement of adhesives at key structural interfaces maintains reliability without significantly increasing manufacturing complexity.
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 solution effectively narrows the spectral linewidth, reducing chromatic aberration and maintaining the reliability of the gas laser device, ensuring high-resolution output for semiconductor manufacturing.
Implementation Method 1
a prism; a mirror including a reflective surface... the reflective surface reflecting light transmitted through the prism
Implementation Method 2
a grating that wavelength-disperses the light reflected by the reflective surface
Implementation Method 3
a mirror including a reflective surface... the reflective surface reflecting light transmitted through the prism
Data Source
AI summary
A line narrowing module includes: a prism; a mirror including a reflective surface, first and second adjacent surfaces, and an opposing surface; a grating wavelength-dispersing light reflected by the reflective surface; a holding part holding the mirror; a first adhesive provided between the holding part and the first adjacent surface or between the holding part and the opposing surface and bonding the mirror to the holding part; a second adhesive provided between the holding part and the second adjacent surface and bonding the mirror to the holding part; and a driving unit rotating the holding part to rotate the mirror about an axis perpendicular to a plane where the light is wavelength-dispersed. The second adhesive is located on an opposite side of the first adhesive with respect to a center line of the mirror in parallel to the axis.