PURPOSE: To make the unit small-size to improve the resistance to humidity, by forming a vessel, which is provided with a recess part and consists of materials of ceramic, by a specified method and by fitting a quartz oscillation bar and an IC chip, which are manufactured by a specified production method, to the recess part and by sealing the vessel in vacuum or gas.

CONSTITUTION: A base part ot which a quartz oscillation bar 7 should be fitted and a pattern to which an IC chip 8 forming an oscillating circuit should be fitted are provided in the recess part of a vessel 6 which consists of materials of ceramic and is provided with the recess part, and the vessel 6 is formed by calcining a green sheet of ceramic after contracting work. The oscillation bar 7 is manufactured from the quartz plate having a ≤500μm thickness by the production method of lithography. The oscillation bar 7 and the chip 8 are fitted to the recess part of the vessel 6, and a cover 10 consisting of metal, glass, etc. is fayed to seal the vessel 6 in vacuum or gas. Thus, the oscillating unit becomes small-size, and the resistance to humidity is improved. Further, production processes of the oscillation bar 7 and the chip 8 are made common to reduce the cost.