Ceramic device

摘要

A ceramic device is disclosed that has a silicon base plate, a first ceramic film formed on a first surface of the silicon base plate, a second ceramic film formed on a second surface of the silicon base plate opposite to the first surface, and an operation opening formed in the silicon base plate between the first and second surfaces. A surface portion of the first ceramic film exposed to the operation opening Is a mirror surface having 0.05 micrometers or less of center line average height Ra. A mirror surface keeping film can be formed between the first surface of the silicon base plate and the first ceramic film for keeping a mirror surface in an etching step to etch the silicon base plate, and the silicon base plate can be reduced partially in the etching step for forming an operation opening thereby exposing a corresponding portion of the mirror surface keeping film to the operation opening.