| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method for a tuning-fork type crystal vibration piece whereby, in the formation of a tuning-fork arm of the vibration piece, it is possible to improve increase in a CI value of the crystal vibration piece due to a shape difference between left and right tuning-fork arms, and facilitate a balance adjustment of the tuning-fork arms.SOLUTION: A method includes the steps to form a tuning-fork shape on a Z plate crystal wafer, where the shape includes a first tuning-fork arm 4 and a second tuning-fork arm 5, extended from a tuning-fork base part toward +Y' direction, and then form an electrode film on the surface of a tuning-fork type crystal vibration piece and form a metal film as a weight for frequency adjustment at the edges of the first tuning-fork arm and the second tuning-fork arm by means such as sputtering or vapor deposition for forming a weight part 7. A laser beam is radiated at the weight part for trimming the metal film to adjust the frequency of the tuning-fork type crystal vibration piece to a predetermined frequency. The weights at the first tuning-fork arm and the second tuning-fork arm are trimmed uniformly until the adjusted frequency becomes 1000 ppm short of a predetermined frequency target value. The adjustment for the remaining 1000 ppm is processed by trimming only the weight part of the first tuning-fork arm to balance the weights of the first tuning-fork arm and the second tuning-fork arm. |
