Abstract
We obtained an accurate relationship between the leaky surface acoustic wave (LSAW) velocities and TiO2 concentrations. Such a relationship is needed for the line-focus-beam ultrasonic material characterization (LFB-UMC) system as a new technology for evaluating the coefficient of thermal expansion (CTE) of ultra-low-expansion glasses with extremely high precision. Using commercially available TiO2-SiO2 glass with periodic striae, averaged velocities for LSAW propagation parallel to the striae plane at 225 MHz and averaged TiO2 concentrations by X-ray fluorescence analysis were measured on the surface of seven specimen substrates prepared perpendicular to the striae plane. The obtained sensitivity of LSAW velocity to TiO2 concentration was -0.0601 wt%/(m/s), and the measurement resolution was estimated to be ±0.0084wt% for ±2σ (σ: standard deviation) from the LSAW velocity measurement resolution of ±0.14 m/s. The TiO2 concentration for the standard TiO 2-SiO2 glass specimen with a LSAW velocity of 3308.18 m/s for system calibration was determined to be 7.09 wt %. This ultrasonic technology will contribute greatly to the development of the ultra-low-expansion glasses needed for extreme ultraviolet lithography (EUVL) systems.
Original language | English |
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Pages (from-to) | 4511-4515 |
Number of pages | 5 |
Journal | Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers |
Volume | 45 |
Issue number | 5 B |
DOIs | |
Publication status | Published - 2006 May 25 |
Keywords
- CTE evaluation
- Chemical composition analysis
- Extreme ultraviolet lithography system
- Leaky surface acoustic waves
- Line-focus-beam ultrasonic material characterization system
- TiO -doped SiO glass
- Velocity measurement
ASJC Scopus subject areas
- Engineering(all)
- Physics and Astronomy(all)