Abstract: The disclosed technology generally relates to quartz crystal devices and more particularly to quartz crystal devices configured to vibrate in torsional mode. In one aspect, a quartz crystal device configured for temperature sensing comprises a fork-shaped quartz crystal comprising a pair of elongate tines laterally extending from a base region in a horizontal lengthwise direction of the fork-shaped quartz crystal, wherein each of the tines has formed on one or both of opposing sides thereof a pair of vertically recessed groove structures laterally elongated in the horizontal lengthwise direction, wherein the pair of groove structures are separated in a horizontal widthwise direction by a line structure.

Abstract: The disclosed technology generally relates to quartz crystal devices and more particularly to quartz crystal devices configured to vibrate in torsional mode. In one aspect, a quartz crystal device configured for temperature sensing comprises a fork-shaped quartz crystal comprising a pair of elongate tines laterally extending from a base region in a horizontal lengthwise direction of the fork-shaped quartz crystal. Each of the tines has formed on one or both of opposing sides thereof a vertically protruding line structure laterally elongated in the horizontal lengthwise direction. The quartz crystal device further comprises a first electrode and a second electrode formed on the one or both of the opposing sides of each of the tines and configured such that, when an electrical bias is applied between the first and second electrodes, the fork-shaped quartz crystal vibrates in a torsional mode in which each of the tines twists about a respective axis extending in the horizontal lengthwise direction.

Abstract: The disclosed technology generally relates to quartz crystal devices and more particularly to quartz crystal devices configured to vibrate in torsional mode. In one aspect, a quartz crystal device configured for temperature sensing comprises a fork-shaped quartz crystal comprising a pair of elongate tines laterally extending from a base region in a horizontal lengthwise direction of the fork-shaped quartz crystal, wherein each of the tines has formed on one or both of opposing sides thereof a pair of vertically recessed groove structures laterally elongated in the horizontal lengthwise direction, wherein the pair of groove structures are separated in a horizontal widthwise direction by a line structure.

Abstract: The disclosed technology generally relates to packaging a quartz crystal, and more particularly to bonding a quartz crystal using sintering silver paste. In one aspect, a method of packaging a quartz crystal comprises attaching a quartz crystal to a package substrate using one or more silver paste layers comprising silver particles. The method additionally comprises sintering the silver paste in a substantially oxygen-free atmosphere and at a sintering temperature sufficient to cause sintering of the silver particles. The sintering is such that the quartz crystal exhibits a positive drift in resonance frequency of the quartz crystal over time. The method further comprises hermetically sealing the quartz crystal in the package substrate.

Abstract: The disclosed technology generally relates to quartz crystal devices and more particularly to quartz crystal devices configured to vibrate in torsional mode. In one aspect, a quartz crystal device configured for temperature sensing comprises a fork-shaped quartz crystal comprising a pair of elongate tines laterally extending from a base region in a horizontal lengthwise direction of the fork-shaped quartz crystal. Each of the tines has formed on one or both of opposing sides thereof a vertically protruding line structure laterally elongated in the horizontal lengthwise direction. The quartz crystal device further comprises a first electrode and a second electrode formed on the one or both of the opposing sides of each of the tines and configured such that, when an electrical bias is applied between the first and second electrodes, the fork-shaped quartz crystal vibrates in a torsional mode in which each of the tines twists about a respective axis extending in the horizontal lengthwise direction.

Abstract: Embodiments of the present disclosure are directed to a piezoelectric resonator. The resonator can have a base defining at least a first base portion and a second base portion and two or more vibrating arms projecting from the first base portion, the first vibrating arm being substantially parallel to the second vibrating arm. The resonator can define a generally planar first main surface and a generally planar second main surface defined by the base and the first and second vibrating arms wherein the first main surface is generally parallel to the second main surface. At least one groove can be formed in at least one of the first and second main surfaces of each of the first and second vibrating arms. The resonator can further have at least one vibration isolation arm projecting from the base, the vibration isolation arm being approximately perpendicular to the two or more vibrating arms.

Abstract: In a quartz crystal microresonator of the type including first and second stem portions, a pair of integral tines extending between the stem portions, a slot between the tines, the slot having opposed crotches where the tines join the stem portions, and a plurality of electrodes mounted on each of the tines, spaced along the lengths thereof, the electrodes being adapted for receipt of an AC voltage for causing the tines to oscillate, there are disclosed several different electrode configurations to optimize resonator performance when operating in the fundamental and first and second overtone flexure modes. The electrodes change polarity along the length of the tines at points where the second derivative of displacement changes polarity.

Abstract: An improved mounting apparatus and method for a piezoelectric tuning fork (10) of the type made from a rectangular plate of quartz or similar material, the fork having a stem portion (12) and a pair of tines (14, 16) extending from the stem and defining between them a crotch (18) where they join the stem. The stem is supported on a pedestal (20-36) in such a way that the forwardmost edge (38) of the pedestal is spaced a distance d (in mils) having a magnitude in the range of 2565n/f to 3135n/f, where n is an integer and f is the fundamental frequency of the tuning fork in kilohertz. Improved suppression of overtone components is achieved during operation in the fundamental mode.

Abstract: An improved piezoelectric tuning fork (12) is disclosed in which the electrodes which drive the tuning fork (30, 32, 34; 36, 38, 40; 42, 48, 50; 52, 54, 56; 58, 60, 62; 64, 66, 68) are positioned along the tines (16, 18) so as to optimize operation at the second overtone frequency.

Abstract: A piezoelectric tuning fork microresonator advantageously is mounted in a package having a transparent region through which the microresonator can be tuned using a laser beam selectively to remove portions of weights provided on the tuning fork tine ends. The laser, located external to the package, may be controlled automatically in response to the output of an oscillator circuit using the microresonator as a frequency standard. The package also may house electronic microcircuitry and may include a capacitor using the package wall as a dielectric. When used with the microresonator in an oscillator circuit, the capacitor enables the frequency to be adjusted slightly by shorting together capacitor plate sections on the outside of the package. A batch fabrication technique is disclosed for automatically assembling many such packages on a single scored, optionally transparent substrate.