Abstract: In the disclosed piezoelectric devices a piezoelectric frame includes a vibrating piece. An excitation electrode is formed on the vibrating piece. An outer frame portion surrounds the vibrating piece and includes an extraction electrode connected to the excitation electrode. A package base is bonded to one surface of the outer frame portion and includes a connection electrode connected to the extraction electrode. The package base includes an external terminal formed on a surface thereof opposite the surface on which the connection electrodes are formed. Through-hole conductors connected the connection electrodes with respective external terminals. A lid is bonded to an opposing surface of the piezoelectric frame. An exhaust channel is in communication with the extraction electrode adjacent the through-hole conductors.

Abstract: A crystal unit includes: a crystal blank in which a depression which function as a vibration region is formed; first and second excitation electrodes formed on both principle surfaces, respectively, of the crystal blank in the vibration region; first and second extending electrodes provided so as to extend from the first and second excitation electrodes, respectively, toward the outer periphery of the crystal blank; and a receptacle body. Bonding of the first extending electrode with eutectic alloy at one point of the outer periphery of the crystal blank electrically and mechanically connects the crystal blank to the receptacle body with the one point as the fixed end. The second extending electrode extends as far as the position of the fixed end and is electrically connected to the receptacle body by wire bonding at the position of the fixed end.

Abstract: In a crystal oscillator having a crystal blank, and an IC chip having integrated therein an oscillation circuit, the crystal blank has a first excitation electrode disposed on its first principal surface, and an extension electrode extended from the first excitation electrode to a peripheral region of the crystal blank, and folded back to the second principal surface. A first and a second crystal connection terminal are disposed on a first principal surface of the IC chip, and the second crystal connection terminal extends to a central region on the first principal surface of the IC chip to constitute a second excitation electrode. The extension electrode is secured to the first crystal connection terminal through a bump, such that the second principal surface of the crystal blank opposes the first principal surface of the IC chip, thereby holding the crystal blank in parallel with the first principal surface of the IC chip. The crystal blank is excited by the first and the second excitation electrodes.

Abstract: To provide a tuning fork type quartz resonator having a low CI value and a quartz resonator package provided with the quartz resonator. A silicon material lower in specific gravity and stiffness than those of conventionally used gold (Au) is used as an electrode material for an electrode pattern such as excitation electrodes for making the tuning fork type quartz resonator generate tuning fork oscillation. By this structure, the quartz resonator is made easier to oscillate so that the oscillation loss (CI value) can be lowered during conversion of electric energy into tuning fork oscillation.

Abstract: A crystal unit for high frequency use includes: a crystal blank having a central portion that is used as a vibration region and a peripheral portion that surrounds the central portion and that is provided with a greater thickness than the central portion; a pair of excitation electrodes provided respectively on both major surface of the crystal blank in said vibration region; a pair of extending electrodes led out from the pair of excitation electrodes toward ends of the crystal blank, respectively; and an opposition region in which the extending electrodes overlap each other with the crystal blank interposed. Each of the extending electrodes connects to a corresponding excitation electrode over at least half of the outer circumference of the excitation electrode, and the thickness of the crystal blank is greater in the opposition region than in the vibration region.

Abstract: A crystal unit comprises an AT-cut crystal blank, and an excitation electrode formed on each of opposing main surfaces of the crystal blank in an oscillation region of the crystal blank. The ratio b/a is 0.014 or less, and preferably 0.012 or less where a represents the thickness of the crystal blank in the oscillation region and b represents the thickness of the excitation electrode. The thickness a is typically 5 ?m or less.

Abstract: A high-frequency quartz crystal unit includes a quartz crystal blank having a hole defined in at least one principal surface thereof, providing a resonating region in a portion of the crystal blank which is made thinner by the hole, excitation electrodes disposed respectively on opposite principal surfaces of the crystal blank in the resonating region, extension electrodes extending respectively from the excitation electrodes to respective first and second positions on an outer peripheral portion of the crystal blank, and a casing. The crystal blank has a fixed end electrically and mechanically connected to the casing by eutectic alloy in the first position. The crystal blank has a free end on which the extension electrodes are electrically connected to the casing by wire bonding in the second position.

Abstract: In a crystal oscillator having a crystal blank, and an IC chip having integrated therein an oscillation circuit, the crystal blank has a first excitation electrode disposed on its first principal surface, and an extension electrode extended from the first excitation electrode to a peripheral region of the crystal blank, and folded back to the second principal surface. A first and a second crystal connection terminal are disposed on a first principal surface of the IC chip, and the second crystal connection terminal extends to a central region on the first principal surface of the IC chip to constitute a second excitation electrode. The extension electrode is secured to the first crystal connection terminal through a bump, such that the second principal surface of the crystal blank opposes the first principal surface of the IC chip, thereby holding the crystal blank in parallel with the first principal surface of the IC chip. The crystal blank is excited by the first and the second excitation electrodes.

Abstract: A crystal unit has a crystal blank having a hole defined in at least one principal surface thereof, the crystal blank having a region of a reduced thickness including the hole, the region serving as a vibrating region, excitation electrodes disposed respectively on opposite principal surfaces of the crystal blank in the vibrating region, extension electrodes extending respectively from the excitation electrodes to respective opposite ends of one side of the crystal blank, and a casing having a step formed therein. The opposite ends of the one side of the crystal blank are fixed to the step by a joining member. The crystal blank has a notched portion defined therein between the one side and the vibrating region, the notched portion extending from at least one transverse edge of the crystal blank in a transverse direction of the crystal blank.

Abstract: A crystal unit includes: a crystal blank in which a depression which function as a vibration region is formed; first and second excitation electrodes formed on both principle surfaces, respectively, of the crystal blank in the vibration region; first and second extending electrodes provided so as to extend from the first and second excitation electrodes, respectively, toward the outer periphery of the crystal blank; and a receptacle body. Bonding of the first extending electrode with eutectic alloy at one point of the outer periphery of the crystal blank electrically and mechanically connects the crystal blank to the receptacle body with the one point as the fixed end. The second extending electrode extends as far as the position of the fixed end and is electrically connected to the receptacle body by wire bonding at the position of the fixed end.

Abstract: A crystal unit for high frequency use includes: a crystal blank having a central portion that is used as a vibration region and a peripheral portion that surrounds the central portion and that is provided with a greater thickness than the central portion; a pair of excitation electrodes provided respectively on both major surface of the crystal blank in said vibration region; a pair of extending electrodes led out from the pair of excitation electrodes toward ends of the crystal blank, respectively; and an opposition region in which the extending electrodes overlap each other with the crystal blank interposed. Each of the extending electrodes connects to a corresponding excitation electrode over at least half of the outer circumference of the excitation electrode, and the thickness of the crystal blank is greater in the opposition region than in the vibration region.

Abstract: A crystal unit comprises an AT-cut crystal blank, and an excitation electrode formed on each of opposing main surfaces of the crystal blank in an oscillation region of the crystal blank. The ratio b/a is 0.014 or less, and preferably 0.012 or less where a represents the thickness of the crystal blank in the oscillation region and b represents the thickness of the excitation electrode. The thickness a is typically 5 ?m or less.

Abstract: A high-frequency quartz crystal unit includes a quartz crystal blank having a hole defined in at least one principal surface thereof, providing a resonating region in a portion of the crystal blank which is made thinner by the hole, excitation electrodes disposed respectively on opposite principal surfaces of the crystal blank in the resonating region, extension electrodes extending respectively from the excitation electrodes to respective first and second positions on an outer peripheral portion of the crystal blank, and a casing. The crystal blank has a fixed end electrically and mechanically connected to the casing by eutectic alloy in the first position. The crystal blank has a free end on which the extension electrodes are electrically connected to the casing by wire bonding in the second position.

Abstract: A crystal unit has a crystal blank having a hole defined in at least one principal surface thereof, the crystal blank having a region of a reduced thickness including the hole, the region serving as a vibrating region, excitation electrodes disposed respectively on opposite principal surfaces of the crystal blank in the vibrating region, extension electrodes extending respectively from the excitation electrodes to respective opposite ends of one side of the crystal blank, and a casing having a step formed therein. The opposite ends of the one side of the crystal blank are fixed to the step by a joining member. The crystal blank has a notched portion defined therein between the one side and the vibrating region, the notched portion extending from at least one transverse edge of the crystal blank in a transverse direction of the crystal blank.

Abstract: A crystal blank for use as a vibrator and a reinforcing plate are joined by direct bonding without an interposed adhesive to form a quartz crystal unit. Through-holes are provided in the reinforcing plate by etching with hydrofluoric acid. Excitation electrodes are formed on both major surfaces of the quartz crystal blank corresponding to the through-holes. An AT-cut quartz crystal plate is preferably used as the crystal blank. The reinforcing plate may be, for example, a Z-cut quartz crystal plate, an AT-cut quartz crystal plate, or a glass plate.

Abstract: A gate insulating film is formed on a main surface of a semiconductor substrate. A conductive layer P1 including a gate region G1 and a conductive layer P2 including a gate region G2 are formed on the gate insulating film. A diffusion regions D1, S, and D2 are formed with gate regions G1 and G2 interposed therebetween. The conductive layer P1 and the diffusion region D2 are put in contact with each other and the conductive layer P2 and the diffusion region D1 are put in contact with each other. On the main surface region of the substrate corresponding to the conductive layer P1, a buried diffusion layer BD1 of the same conductive type as the diffusion region S is formed contiguously to the diffusion region S. On the main surface region of the substrate corresponding to the conductive layer P2, a buried diffusion layer BD2 of the same conductive type as the diffusion region S is formed contiguously to the diffusion region S. Then, the diffusion region S is grounded.