Method for manufacturing quartz crystal unit and electronic apparatus having quartz crystal unit

摘要

In a method for manufacturing a quartz crystal unit, a quartz crystal tuning fork resonator is formed by etching a quartz crystal wafer to form a quartz crystal tuning fork base and first and second quartz crystal tuning fork tines connected to the quartz crystal tuning fork base. The quartz crystal tuning fork resonator has a piezoelectric constant e'₁₂ within a range of 0.12 C/m² to 0.19 C/m² in the absolute value to drive the quartz crystal tuning fork resonator. An electrode is disposed on each of two of side surfaces of each of the first and second quartz crystal tuning fork tines so that the electrodes disposed on the side surfaces of the first quartz crystal tuning fork tine have an electrical polarity opposite to an electrical polarity of the electrodes disposed on the side surfaces of the second quartz crystal tuning fork tine. The quartz crystal tuning fork resonator is mounted on a mounting portion of a case.