Seiko Epson Corporation

Epson Toyocom Corporation

Toyo Communication Equipment Co., Ltd.

Nec Electronics Corporation

Tsuyoshi Ohshima

Shin Hasegawa

Noriyuki Watanabe

Yasutaka Nakashiba

Masayuki Ishikawa

Susumu Kurosawa

Tomio Satoh

Yuki Fujimoto

Shigehisa Kurogo

Jun Matsuoka

Toshiyasu Takasugi

Masahiro Onuki

A method of manufacturing a piezoelectric vibrator comprises supporting a piezoelectric vibration element in a case by a conductive bonding member, the piezoelectric vibration element having a metal layer formed on a piezoelectric substrate formed of a thickness shear based piezoelectric material, and adding or reducing a thickness of the metal layer to adjust a resonant frequency of the piezoelectric vibration element to a predetermined value. The method also comprises leaving the case into an atmosphere filled with vapor of a material having a nonbonding electron pair, making the metal layer resultantly exposed to the vapor subject to chemical absorption with the material having the nonbonding electron pair, and hermetically encapsulating the case in a state substituted by an inert gas atmosphere.

Method of manufacturing a piezoelectric vibrator

A piezoelectric vibration element that includes a piezoelectric substrate formed of a thickness shear based piezoelectric material and a metal layer formed on a surface of the piezoelectric substrate. In the piezoelectric vibration element, a surface of the metal layer is covered by a layer formed by chemical absorption with a material having a nonbonding electron pair.

A method of stabilizing a frequency of a piezoelectric vibration element includes: disposing the piezoelectric vibration element in an atmosphere of a vapor of a ring-shaped dimethylpolysiloxane molecule, the piezoelectric vibration element having a metal layer on a surface of a piezoelectric substrate formed of a thickness slip based piezoelectric material; and making the ring-shaped dimethylpolysiloxane molecule subject to chemical absorption with a surface of the metal layer to form a layer of the ring-shaped dimethylpolysiloxane molecule.

Method of stabilizing a frequency of a piezoelectric vibration element

Deterioration in frequency stability with time in a conventional piezoelectric oscillator using an accumulation type MOS capacitance element is improved. A P-channel transistor type or an N-channel transistor type is used as a MOS capacitance element in a variable capacitance circuit used in a piezoelectric oscillator. A bias voltage is applied between P-type or N-type extraction electrodes formed in source and drain regions and an N-type extraction electrode provided in an N-well region or a P-type extraction electrode provided in a P-well region. Instability in the MOS capacitance element with time is thus eliminated.

Piezoelectric-oscillator

A piezoelectric vibration element is provided which includes a piezoelectric substrate formed of a thickness slip based piezoelectric material and a metal layer formed on a surface of the piezoelectric substrate. In the piezoelectric vibration element, a surface of the metal layer is covered by a layer formed by chemical absorption with a material having a nonbonding electron pair.

Piezoelectric vibration element, piezoelectric vibrator, piezoelectric oscillator, frequency stabilization method, and method of manufacturing the piezoelectric vibrator

A quartz oscillator for quadrature modulation has a quartz oscillating circuit including a transistor, a quartz oscillator, a capacitor, and a resistor, a double-mode quartz filter, a reactance element, and an amplifier. The quartz oscillator is constituted so that an output of the quartz oscillating circuit is a first output, and its output is connected to one terminal of the double-mode quartz filter where a common electrode is grounded. The reactance element is connected in parallel between the other terminal and the ground, and a second output is obtained from a connected point via the amplifier.

Piezoelectric oscillator for quadrature modulation

A piezoelectric oscillation circuit has a series circuit composed of a capacitor Cbe as a part of a load capacitance and a capacitor Ce inserted and connected between a base of an oscillation transistor TRand the ground, and has an emitter resistor Re connected to a connection midpoint A of the series circuit and an emitter of the oscillation transistor TR. Further, a base bias circuit composed of a resistor RBand a resistor RBis connected to a base of the oscillation transistor TR, has a piezoelectric element Xtal and a capacitor Cinserted and connected in series between the base of the oscillation transistor TRand the ground, and further has a resistor Rc connected to a collector of the oscillation transistor TRtogether with the power supply voltage Vcc line, and has a capacitor Cce connected between the collector and the emitter.

Growing community of inventors

Chigasaki, Japan

Tsuyoshi Ohshima