PURPOSE: To provide an anisotropic etching method for barium strontium titanate.
CONSTITUTION: A barium strontium titanate substrate 34 is immersed into a liquid atmosphere (for example, hydroacid chloride 30 of 12 mol in concn.) and is illuminated with the electromagnetic radiation (for example, converged visible/UV electromagnetic radiation 24) emitted by a radiation source (for example, a mercury xenon arc lamp 20 of 200 Watt). A window 26 which is intrinsically transparent to the converged electromagnetic radiation 24 permits the arrival of the radiated energy at the titanate substrate 34. An etching mask 32 may be arranged between the radiation source 20 and the substrate 34. The titanate substrate 34 and the liquid atmosphere 30 are kept at a nominal temp. (for example, 25°C). The titanate is hardly etched by the liquid atmosphere without illumination. The etching rate increases intrinsically when the barium strontium titanate is illuminated.
HAWAADO AARU BERATAN
SUKOTSUTO AARU SAMAAFUERUTO
