Piezoelectric resonator element, piezoelectric device, method of manufacturing the same, cellular phone device utilizing piezoelectric device, and electronic equipment utilizing piezoelectric device

摘要

A piezoelectric resonator element is provided including a base portion and a plurality of resonating arms extending from the base portion. A notch part is formed in the base portion. Grooves are formed in the front and back surfaces of the resonating arms. A driving electrode is provided at least in the grooves of the resonating arms. The driving electrode has a lower layer and an electrode layer formed on the lower layer. The thickness t of the lower layer is in the range 0.07<t<0.3 micrometers.