The Belle II A-RICH counter requires transparent silica aerogel Cherenkov radiators.
Required refractive index of hydrophobic aerogel tiles is approximately 1.05.
Mass production of large-area (18 cm × 18 cm × 2 cm), crack-free aerogel tiles is vital.
A method for producing aerogel tiles satisfying all requirements is established.
Crack-free aerogel tiles are ensured by pressure control in the supercritical drying.