Imprint Apparatus Substrate Tilt Measurement Using Small Probe
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing imprint techniques face challenges in accurately measuring the tilt of a substrate surface during the imprint process, especially when the substrate stage base surface is deformed, leading to difficulties in achieving parallel contact between the mold and the substrate, which results in defects and non-uniformity in pattern formation.
Innovation Solution
An imprint apparatus equipped with a first measurement unit that uses a probe with a smaller contact surface area than the mold to measure the height distribution of the substrate at the contact position, allowing for accurate tilt measurement without the need for additional optical measurement systems near the imprint position, and a second measurement unit for non-contact height measurement to correct the tilt.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a mold with large contact surface area is used to measure substrate height, then the measurement covers a larger area, but convex portions between which concave portions are present cannot be detected, leading to inaccurate tilt measurement
Solution Approach 1:
The measurement process is segmented into two distinct steps: first, a probe with small contact area measures height at multiple discrete positions including convex portions; second, these discrete measurements are used to calculate the tilt of the substrate surface. This segmentation allows detection of all substrate features without the limitations of a single large-contact measurement.
Solution Approach 2:
A probe with small contact surface area is introduced as an intermediary measurement tool between the substrate and the measurement system. This probe can access and measure convex portions that a large-contact mold cannot detect, providing comprehensive height data for accurate tilt calculation.
2Measurement precision
If an optical measurement unit is added near the imprint position to measure substrate surface, then measurement accuracy is improved, but the device complexity and design difficulty increase due to existing mechanisms in the limited space
Solution Approach 1:
The existing imprint apparatus mechanisms (substrate stage movement unit, mold movement unit) are utilized to perform the measurement function. The substrate stage moves the substrate to positions where height measurements are taken, and the mold movement unit controls the measurement process, eliminating the need for dedicated optical measurement hardware.
Solution Approach 2:
Existing components of the imprint apparatus are given multiple functions: the substrate stage movement unit serves both for positioning during imprinting and for positioning during height measurement; the mold movement unit controls both the imprinting process and the measurement process. This multi-functionality avoids adding complex dedicated measurement systems.
3Ease of operation
If the substrate stage base surface is used as reference for tilt measurement, then the measurement process is simplified, but deformation of the base surface causes the reference to vary, making accurate parallel pressing difficult
Solution Approach 1:
Instead of directly using the potentially deformed base surface as the reference, the system creates a copied reference model by measuring the actual substrate surface height at multiple positions and calculating the tilt based on these measurements. This copied reference accurately reflects the true substrate orientation regardless of base surface deformation.
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 precise alignment of the substrate and mold, reducing defects and improving the uniformity of pattern formation by accurately determining the tilt of the substrate surface, even when the substrate stage base surface is deformed, thereby enhancing the parallelization and productivity of the imprint process.
Implementation Method 1
The first measurement unit measures a height of the substrate by bringing a probe into contact with a surface of the substrate
Implementation Method 2
the mold is irradiated with ultraviolet light and the photo-curable composition is cured
Data Source
AI summary
An imprint apparatus that forms a curable composition on a substrate using a mold includes a first measurement unit configured to measure a height distribution of the substrate at a contact position where the mold and the curable composition are brought into contact with each other. The first measurement unit measures a height of the substrate by bringing a probe into contact with a surface of the substrate, the probe having a contact surface area smaller than a contact surface area of the mold.