TY - GEN
T1 - Evaluation of TiO2-SiO2 ultra-low-expansion glass fabricated by the soot method using the line-focus-beam ultrasonic material characterization system
AU - Kushibiki, Jun Ichi
AU - Arakawa, Mototaka
AU - Ueda, Tetsuji
AU - Fujinoki, Akira
PY - 2008/12/1
Y1 - 2008/12/1
N2 - In this paper, we tried to fabricate a TiO2-doped SiO 2 (TiO2-SiO2) glass ingot by the soot method, and homogenized the glass ingot by the zone-melting method. Homogeneities of the specimens were evaluated by measuring leaky surface acoustic wave (LSAW) velocity using the line-focus-beam ultrasonic material characterization system at 225 MHz. Two-dimensional LSAW velocity distributions having an average velocity of 3304.08 m/s with a maximum velocity difference of 3.85 m/s were measured for a homogenized specimen. Striae were not observed for the specimen. The velocity difference corresponds to 17.0 ppb/K from the sensitivity of the LSAW velocity to the CTE {4.41 (ppb/K)/(m/s)}. However, the velocity distributions excluding the edge parts were within ±1.13 m/s, corresponding to the CTE specification of ±5 ppb/K required for EUVL-grade glass. We also discussed the relationship between LSAW velocities and fictive temperatures by heat-treating a part of the homogenized specimen.
AB - In this paper, we tried to fabricate a TiO2-doped SiO 2 (TiO2-SiO2) glass ingot by the soot method, and homogenized the glass ingot by the zone-melting method. Homogeneities of the specimens were evaluated by measuring leaky surface acoustic wave (LSAW) velocity using the line-focus-beam ultrasonic material characterization system at 225 MHz. Two-dimensional LSAW velocity distributions having an average velocity of 3304.08 m/s with a maximum velocity difference of 3.85 m/s were measured for a homogenized specimen. Striae were not observed for the specimen. The velocity difference corresponds to 17.0 ppb/K from the sensitivity of the LSAW velocity to the CTE {4.41 (ppb/K)/(m/s)}. However, the velocity distributions excluding the edge parts were within ±1.13 m/s, corresponding to the CTE specification of ±5 ppb/K required for EUVL-grade glass. We also discussed the relationship between LSAW velocities and fictive temperatures by heat-treating a part of the homogenized specimen.
KW - CTE evaluation
KW - Euvl system
KW - Fictive temperature
KW - Heat treatment
KW - Homogenization process
KW - Leaky surface acoustic waves
KW - Line-focus-beam ultrasonic material characterization system
KW - TiO-siO ultra-low-expansion glass
KW - Velocity measurement
UR - http://www.scopus.com/inward/record.url?scp=77955379023&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77955379023&partnerID=8YFLogxK
U2 - 10.1117/12.772259
DO - 10.1117/12.772259
M3 - Conference contribution
AN - SCOPUS:77955379023
SN - 9780819471062
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Emerging Lithographic Technologies XII
T2 - Emerging Lithographic Technologies XII
Y2 - 26 February 2008 through 28 February 2008
ER -