Generalization of the classical 'parallel' condition: zero-wavelength-dispersion 'counter' profile measurement

The surface and thickness distribution measurement for transparent film is of interest for electronics and packaging materials. Structured illumination microscopy (SIM) is a prospective technique for measuring film due to its high accuracy and efficiency. However, when the distance between adjacent layers becomes close, the peaks of the modulation depth response (MDR) start to overlap and interfere with the peak extraction, which restricts SIM development in the field of film measurement. In this paper, an iterative peak separation algorithm is creatively applied in the SIM-based technique, providing a precise peak identification even as the MDR peaks overlap and bend into one. Compared with the traditional method, the proposed method has a lower detection threshold for thickness. The experiments and theoretical analysis are elaborated to demonstrate the feasibility of the mentioned method.

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Intelligent Profile Measurement for Wide-Area Resist Surface Using Multi-Sensor AFM System

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.381-382.407 ◽

2008 ◽

Vol 381-382 ◽

pp. 407-410

Author(s):

Shu Jie Liu ◽

K. Watanabe ◽

Satoru Takahashi ◽

Kiyoshi Takamasu

Keyword(s):

Thin Film ◽

Semiconductor Industry ◽

Surface Profile ◽

Vertical Direction ◽

Profile Measurement ◽

Measuring Device ◽

Scanning Method ◽

Angle Measuring ◽

Experimental Apparatus ◽

Sensor Errors

In the semiconductor industry, a device that can measure the surface-profile of photoresist is needed. Since the photoresist surface is very smooth and deformable, the device is required to measure vertical direction with nanometer resolution and not to damage it at the measurement. We developed the apparatus using multi-cantilever and white light interferometer to measure the surface-profile of thin film. But, this system with scanning method suffers from the presence of moving stage and systematic sensor errors. So, in this paper, an error separation approach used coupled distance sensors, together with an autocollimator as an additional angle measuring device, was consulted the potentiality for self-calibration of multi-cantilever. Then, according to this method, we constructed the experimental apparatus and do the measurement on the resist film. The results demonstrated the feasibility that the constructed multi-ball-cantilever AFM system combined with an autocollimator could measure the thin film with high accuracy.

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Harmonic Analysis on Low Quality Tidal Data

Volume 8B: Ocean Engineering ◽

10.1115/omae2014-24014 ◽

2014 ◽

Author(s):

Joost den Haan

Keyword(s):

Harmonic Analysis ◽

Three Dimensional ◽

Measurement Data ◽

Tidal Energy ◽

Energy Yield ◽

Profile Measurement ◽

Current Profile ◽

Tidal Power ◽

Data Set ◽

Tidal Forcing

The aim of the study is to devise a method to conservatively predict a tidal power generation based on relatively short current profile measurement data sets. Harmonic analysis on a low quality tidal current profile measurement data set only allowed for the reliable estimation of a limited number of constituents leading to a poor prediction of tidal energy yield. Two novel, but very different approaches were taken: firstly a quasi response function is formulated which combines the currents profiles into a single current. Secondly, a three dimensional vectorial tidal forcing model was developed aiming to support the harmonic analysis with upfront knowledge of the actual constituents. The response based approach allowed for a reasonable prediction. The vectorial tidal forcing model proved to be a viable start for a full featuring numerical model; even in its initial simplified form it could provide more insight than the conventional tidal potential models.

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