| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a crystal oscillator capable of maintaining a constant oscillation frequency with a small characteristic variation on receiving X-ray irradiation by X-ray inspection etc. <P>SOLUTION: The crystal oscillator includes: a vessel body 1; a crystal chip 2 being housed in a first recess 1a formed on one principal surface of the vessel body 1 and airtight sealed in the first recess 1a by a metal cover 7; and an IC chip 3 having an integrated electronic circuit at least including an oscillation circuit using the crystal chip 2, and being housed in a second recess 1b formed on the other principal surface of the vessel body 1. The IC chip 3 is fastened on the bottom face of the second recess 1b by flip chip bonding in such a manner that the circuit formation surface of the IC chip 3 faces the bottom face of the second recess 1b. A radiation ray protection film 12 is formed on a principal surface of the IC chip 3 other than the circuit formation surface. <P>COPYRIGHT: (C)2012,JPO&INPIT |
