PRODUCTION OF OPTICAL CIRCUIT

摘要

PURPOSE:To prevent the penetration of the material of a mask and to execute the satisfactory masking by penetrating a liquid contg. the particles of a glass raw material having <=0.5mu grain size to porous glass prior to masking said glass. CONSTITUTION:The liquid 2 contg. the particles 6 of the glass raw material having <=0.5mu grain size is penetrated into the porous glass prior to masking 3. The satisfactory masking is thereby executed because <=0.5mu particles intrude into the clearances of the porous body to decrease the surface clearance size. The particles of the grain size larger than 0.5mu have such defects as the easy tendency of the particles to settling and the difficulty of dispersion into the liquid and are undesirable. The particles having about 0.01mu grain size are suitable. The lower limit value of the particles is by and large about 0.003mum but is not particularly limited. Mingling of any small particle is equally satisfactory.