Crystal oscillator and method of bonding IC chip useful for fabricating crystal oscillator

A crystal oscillator comprising:

• a vessel main body having a concave portion;
• a cover bonded to the vessel main body to form an encapsulated vessel;
• a crystal blank held within the vessel;
• an IC (integrated circuit) chip containing an oscillation circuit utilizing the crystal blank and having a plurality of terminal electrodes on one major surface thereof;
• and
• a plurality of connection terminal portions formed on a bottom surface of the concave portion so that each of the connection terminal portions corresponds to one of the terminal electrodes, wherein
• the terminal electrodes and the connection terminal portions are bonded to each other through a bump by means of ultrasonic thermocompression bonding so that the IC chip is fixed to the bottom surface, and
• each of the connection terminal portions is formed into a rectangular shape and longitudinal direction of the connection terminal portions are in parallel with one another.

A crystal oscillator comprising:

• a vessel main body having a concave portion;
• a cover bonded to the vessel main body to form an encapsulated vessel;
• a crystal blank held within the vessel;
• an IC (integrated circuit) chip containing a silicon substrate and a circuit provided on the silicon substrate, and having a plurality of terminal electrodes on one major surface thereof;
• and
• a plurality of connection terminal portions formed on a bottom surface of the concave portion so that each of the connection terminal portions corresponds to one of the terminal electrodes, wherein
• the terminal electrodes and the connection terminal portions are bonded to each other through a bump so that the IC chip is fixed to the bottom surface, and
• the terminal electrodes are made of an aluminum layer, a metal layer having a thickness larger than that of the aluminum layer is formed on the terminal electrodes, and the terminal electrodes are bonded to the bump through the metal layer.

A crystal oscillator comprising:

• a vessel;
• a outer electrode for surface mount provided on an external bottom surface and an external side surface of the vessel;
• a crystal blank held within the vessel and having a pair of excitation electrodes;
• an IC (integrated circuit) chip having a pair of crystal electrodes to be electrically connected to the pair of excitation electrodes, containing an oscillation circuit utilizing the crystal blank, and fixed within the vessel;
• a first pair of relaying electrodes electrically connected to the pair of excitation electrodes and led to the external side surface of the vessel;
• and
• a second pair of relaying electrodes provided to be independent of the first pair of relaying electrodes, electrically connected to the pair of crystal electrodes, and led to the external side surface of the vessel.

A method of bonding an IC (integrated circuit) chip useful for fabricating a crystal oscillator, the crystal oscillator including a vessel main body having a concave portion, a cover bonded to the vessel main body to form an encapsulated vessel, a crystal blank held within the vessel, the IC chip containing an oscillation circuit utilizing the crystal blank and having a plurality of terminal electrodes on one major surface thereof, and a plurality of connection terminal portions formed on a bottom surface of the concave portion so that each of the connection terminal portions corresponds to one of the terminal electrodes, wherein each of the connection terminal portions is formed into a rectangular shape having an identical width, the method comprising the steps of:

• forming a bump on the terminal electrodes
• aligning each of the terminal electrodes with a corresponding one of the connection terminal portions;
• and thereafter
• bonding the terminal electrodes to the connection terminal portions through the bump by means of ultrasonic thermocompression using a ultrasonic wave of which vibration direction is coincident with longitudinal direction of the connection terminal portions.

A method of bonding an IC (integrated circuit) chip useful for fabricating a crystal oscillator, the crystal oscillator including a vessel main body having a concave portion, a cover bonded to the vessel main body to form an encapsulated vessel, a crystal blank held within the vessel, the IC chip containing an oscillation circuit utilizing the crystal blank and having a plurality of terminal electrodes on one major surface thereof, and a plurality of connection terminal portions formed on the bottom surface of the concave portion so that each of the connection terminal portions corresponds to one of the terminal electrodes, wherein each of the connection terminal portions is formed into a rectangular shape and longitudinal direction of the connection terminal portions are in parallel with one another, the method comprising the steps of:

• forming a bump on the terminal electrodes;
• aligning each of the terminal electrodes with a corresponding one of the connection terminal portions;
• and thereafter
• bonding the terminal electrodes to the connection terminal portions through the bump by means of ultrasonic thermocompression bonding using a ultrasonic wave of which vibration direction is coincident with the longitudinal direction of the connection terminal portions.

A method of bonding an IC (integrated circuit) chip useful for fabricating a crystal oscillator, the crystal oscillator including a vessel main body having a concave portion, a cover bonded to the vessel main body to form an encapsulated vessel, a crystal blank held within the vessel, the IC chip containing a silicon substrate and a circuit provided on the silicon substrate and having a plurality of terminal electrodes made of aluminum layer on one major surface thereof, and a plurality of connection terminal portions formed on the bottom surface of the concave portion so that each of the connection terminal portions corresponds to one of the terminal electrodes, the method comprising the steps of:

• forming a metal layer on the terminal electrodes so that the metal layer has a thickness larger than that of the aluminum layer constituting the terminal electrodes;
• forming a bump on the metal layer;
• aligning each of the terminal electrodes with a corresponding one of the connection terminal portions;
• and thereafter
• bonding the terminal electrodes to the connection terminal portions through the bump by means of ultrasonic thermocompression bonding.