Immersion Lithography Apparatus Inclined Platform
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional photolithography processes struggle to produce three-dimensional micro-structures with inclined flanks due to the inability to control inclined angles effectively, limiting the creation of complex micro-structures.
Innovation Solution
An immersion lithography apparatus with a container filled with a liquid of refractive index between 1.4 and 1.8, featuring a platform that can be inclined using a roller system, allowing for both normal and inclined lithography by minimizing the change in incident angle through refractive index matching with the photoresist layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional photolithography apparatus is used, then the structure is simple and easy to operate, but three-dimensional micro-structures with inclined flanks cannot be produced
Solution Approach 1:
The patent introduces a movable platform that can be rotated to different angles, transforming the static conventional photolithography setup into a dynamic system. This allows the apparatus to perform both normal incidence and inclined incidence lithography by simply rotating the platform, thereby achieving versatility without significantly increasing manufacturing complexity
Solution Approach 2:
The patent creates a multi-functional lithography apparatus that can perform both conventional normal incidence lithography and inclined incidence lithography using the same basic equipment. By incorporating a rotatable platform, the single apparatus serves multiple purposes: producing three-dimensional micro-structures with inclined flanks while maintaining the ability to perform standard lithography operations
2Manufacturing precision
If inclined incidence lithography is implemented, then three-dimensional micro-structures with inclined flanks can be formed, but the apparatus complexity increases
Solution Approach 1:
The patent achieves inclined incidence capability through a simple rotatable platform mechanism rather than a complex dedicated inclined lithography system. The platform can be rotated to the required inclination angle and maintained during exposure, providing precise control over the incident light angle while keeping the overall apparatus structure relatively simple
Solution Approach 2:
The rotatable platform acts as an intermediary component that bridges the conventional photolithography apparatus and the desired inclined incidence function. Instead of modifying the entire lithography system, the platform serves as a mediator that enables angle control while maintaining compatibility with existing equipment components
3Measurement precision
If liquid immersion is used with refractive index matching, then the change of incident angle is minimized, but the device complexity and liquid management requirements increase
Solution Approach 1:
The patent utilizes the parameter change of refractive index by selecting a liquid with a specific refractive index (1.4-1.8) that matches the photoresist material. This parameter matching minimizes refraction and maximizes the transmission of light at inclined angles, enabling precise control of the incident angle on the photoresist surface
Solution Approach 2:
The liquid immersion medium acts as an intermediary between the light source and the photoresist layer. By filling the space between these components, the liquid reduces optical interference and refraction, serving as an optical bridge that maintains angle precision while enabling the inclined incidence lithography process
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 the precise formation of three-dimensional micro-structures with inclined flanks by controlling the angle of incidence and refraction, overcoming the limitations of conventional photolithography in creating complex geometries.
Implementation Method 1
refraction occurs when light travels from a medium to another, which usually causes a change of direction of the light or a change of incident angle. In an embodiment of this invention, the refractive index of the liquid is similar to or about equal to a refractive index of the photoresist so that the change of the incident angle may be smaller
Data Source
AI summary
An immersion lithography apparatus including a container, at least a liquid, a platform, a fixture, a roller, a light source, and a filter is provided. The container includes a bottom plate, a plurality of side plates, and a bearing hole penetrated through one of the side plates. The liquid is filled in the container. The platform is immersed in the liquid. The platform includes a pair of axles. The axles are parallel to the bottom plate. One of the axles passes through the bearing hole. The fixture is mounted on the platform for clamping a mask and a wafer. The roller is connected to the axle, passes through the bearing hole, and is operated to rotate the connected axle. The light source generates ultraviolet light to incident on the mask and the wafer. The filter is located between the light source and the fixture.