Imprint Lithography Alignment Grating Offset Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In lithography, accurately aligning patterns on a substrate is crucial for functional device production, but existing methods lack a novel and effective alignment apparatus for imprint lithography, which can lead to misalignment and device malfunction.
Innovation Solution
A method and apparatus using alignment gratings on both the imprint template and substrate, where an alignment radiation beam is directed at the composite grating formed by these gratings, and the relative position is modulated to detect and determine the offset between them, allowing precise alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional photolithography methods are used to achieve smaller features, then resolution can be improved, but manufacturing cost increases significantly
Solution Approach 1:
The patent replaces optical projection systems with mechanical contact-based imprint lithography. A stamp or template is physically pressed against the substrate to transfer patterns, eliminating the need for complex optical systems, high-cost radiation sources, and precise alignment optics required in photolithography. This mechanical approach achieves comparable or better resolution at lower cost.
Solution Approach 2:
The patent changes the fundamental parameter from optical wavelength-limited resolution to mechanical contact resolution. By using physical contact between the stamp and substrate, the resolution is determined by the stamp fabrication precision rather than optical diffraction limits, enabling smaller features without proportionally increasing system cost.
2Manufacturing precision
If alignment apparatus is added to improve pattern alignment, then manufacturing precision improves, but device complexity increases
Solution Approach 1:
The imprint lithography system uses self-alignment through direct physical contact between the stamp and substrate. The stamp's pattern features automatically align with the substrate surface, eliminating the need for separate alignment apparatus, alignment marks, and complex alignment procedures required in photolithography.
Solution Approach 2:
The patent extracts and removes the alignment apparatus component entirely from the lithography system. By using mechanical contact imprinting, the alignment function is inherent in the contact process itself, making separate alignment systems unnecessary and reducing overall device 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
This approach enables accurate alignment of imprint templates with substrates, ensuring proper pattern registration and preventing device malfunction by determining and correcting misalignments, thus improving the reliability of lithographic processes.
Implementation Method 1
detecting a property of alignment radiation which is reflected from the composite grating
Implementation Method 2
bringing the first imprint template alignment grating and the first substrate alignment grating sufficiently close together that they form a composite grating
Data Source
AI summary
A method of determining an offset between an imprint template and a substrate using an alignment grating on the imprint template and an alignment grating on the substrate is disclosed. The method includes bringing the imprint template alignment grating and the substrate alignment grating sufficiently close together such that they form a composite grating, directing an alignment radiation beam at the composite grating while modulating the relative position of the imprint template and the substrate, detecting the intensity of alignment radiation which is reflected from the composite grating, and determining the offset by analyzing modulation of the detected intensity.