
Glossary
|
Accelerometer |
Instruments measuring acceleration, vibration, seismic motion and tilt. |
|
AHRS |
Attitude Heading Reference System (AHRS) combine gyroscopes and accelerometers that provide heading, attitude and yaw information for aircraft. |
|
Anisotropic etching |
Etching which involves different etch rates in different directions in the material |
|
Anodic bonding |
A technique for bonding a glass substrate, which contains movable ions, to an electrically conductive substrate (e.g. silicon) |
|
Axis alignment [mrad] |
The extent to which the accelerometer's true sensitive axis deviates from being perfectly orthogonal to the accelerometer's reference mounting surface when mounted to a flat surface |
|
Bandwidth [Hz] |
Frequency range from DC to F-3dB where the variation of the frequency response is less than –3dB |
|
Bias [mg] |
The accelerometer output at zero g |
|
Bias stability [mg] |
Maximum drift of the bias after extreme variation of external conditions (aging, temperature cycles, shock, vibration) |
|
Bias temperature coefficient [mg/°C] |
Maximum variation of the bias calibration under variable external temperature conditions (slope of the best fit straight line through the curve of bias vs. temperature). Bias Temperature Coefficient is specified between –40°C and +50°C, where temperature behavior is linear |
|
Bulk micromachining |
A Micromachining process where devices are built witch a thickness essentially equal to the full wafer thickness |
|
Capacitive accelerometer |
An accelerometer that uses electrical capacitors to detect movement of a proof mass. |
|
Closed loop electronics |
Electronics used in servo accelerometers that use electrostatic forces to balance inertial forces. Closed loop electronics are used in high precision/ high resolution accelerometers |
|
Cycle time |
Time period of manufacturing parts from raw material to finished products |
|
Dead reckoning system |
Dead reckoning systems allow estimating one's current position based upon a previously determined position. Dead reckoning systems based on inertial sensors are widely used in combination with GPS systems to indicate the position during periods where the GPS has no reliable signal (e.g. in tunnels or in buildings) |
|
Digital full wave system |
Digital full wave systems is the newest technology for seismic imaging. It is expected that full-wave digital technology becomes the new seismic imaging standard in the years ahead. |
|
DOE lenses |
Diffractive optical elements are a special type of lenses using diffractive effects. Colibrys manufactures DOE’s on quartz substrates using MEMS technology. They are mainly used in Photolithographic equipment (steppers) for the manufacturing of Integrated circuits with smallest feature sizes |
|
DRIE |
Deep Reactive Ion Etching is a micromachining process for etching 3 D structures in silicon using a plasma process. |
|
Doping |
Process of intentionally introducing impurities into an extremely pure semiconductor in order to change its electrical properties |
|
Fusion bonding |
A technique for bonding two silicon wafers substrate together. This process is typically used to form capacitive sensors with the movable parts enclosed in a hermetically sealed cavity. |
|
g [m/s2] |
Unit of acceleration, equal to standard value of the earth gravity (Accelerometer specifications and data supplied by Colibrys use 9.80665 m/s²) |
|
GPS |
Global positioning system |
|
Gun hard |
Sensors designed to survive and maintain its performance during the firing of a smart munitions from a gun |
|
Gyroscope |
Instrument that measures angular rotation speed |
|
Harsh environment |
Environment with extreme conditions with respect to vibration, shock, temperature, or radiation |
|
HUMS |
Health usage monitoring system |
|
IMU |
Inertial measurement unit. Sensor system combining gyroscopes and accelerometers used for inertial navigation |
|
Inertial navigation |
An inertial-navigation systemis a navigation aid that uses a computer and motion sensors to continuously track the position, orientation, and velocity (direction and speed of movement) of a vehicle without the need for external references |
|
Inertial sensor |
Sensor used in Inertial navigation systems: (accelerometers and gyroscopes) |
|
IRS |
Inertial reference system |
|
KOH |
Potassium Hydroxyde. Chemical substance used for anisotropic etching of silicon wafers. |
|
MEMS |
Micro electro mechanical systems |
|
MEMS geophone |
Seismic accelerometer replacing electromechanical geophones in seismic applications |
|
MEMS technology |
Technology to manufacture MEMS devices. This technology is mainly used to manufacture sensors and actuators such as pressure sensors, accelerometers, ink-jet print heads and optical light modulators (DPL) |
|
Micro-nano technology |
Designs the broad technology area of products with features in the range from micro to nanometers (micrometer= millionth of a meter, nanometer=billionth of a meter) |
|
Mixed signal electronics |
Electronics circuits combining analog and digital functions. |
|
Motion sensor |
Sensors that detects motion, such as accelerometers and gyroscopes |
|
Multi chip module MCM-D |
A Multi-Chip Module or MCM is a specialized electronic package where multiple integrated circuits (ICs), semiconductor dies or MEMS chips are packaged in a single module |
|
NEXUS |
Nexus is a pan-European Microsystems Association |
|
Noise [mV/√Hz] |
Undesired perturbations in the accelerometer output signal, which are generally uncorrelated with desired or anticipated input accelerations |
|
Non-linearity |
The maximum deviation of accelerometer output from the best linear fit over the full operating range. The deviation is expressed as a percentage of the full-scale output (+AFS). |
|
Optical attenuators |
MEMS devices also called VOA (Variable Optical Attenuator) that are used to control the quantity of light passing from one fibre to an other. |
|
Optical filters |
Optical components to filter light. Colibrys filters are used to control the wavelength of tunable lasers used in telecoms applications |
|
Optical modulators |
Subsystems that allow controlling a large number of individual light beams to form a pattern or an image. |
|
Optical switches |
Components used mainly in telecoms applications to switch optical signals between different fibres |
|
Photolithography |
Manufacturing process used to define structures on wafers. It is a basic process widely used in chip manufacturing |
|
P-Wave |
Pressure Wave: A compression wave also known as a primary wave, a P-wave is a seismic wave that pushes and pulls rocks, contracting and expanding them as it moves through them. |
|
Resolution, threshold [mg] |
Value of the smallest acceleration that can be significantly measured |
|
Resonant frequency nominal [kHz] |
Typical value of the resonant frequency of the mounted system |
|
Scalable process |
Manufacturing Process that is not specific to a particular product but that can be used for a wide range of products |
|
Scale factor sensitivity |
The ratio of the change in output (in volts) to a unit change of the input (in units of acceleration); thus given in mV/g |
|
Scale factor temperature coefficient |
Maximum deviation of the scale factor under variable external temperature conditions; thus given in ppm/°C |
|
Seismic imaging |
Seismic Imaging is a method to image the earth subsurface from reflected seismic waves. The method requires a controlled source of energy such as dynamite or vibrators and an array of seismic sensors such as geophones or high resolution accelerometers. |
|
Seismic sensor |
Acceleration sensor with very high sensitivity able to detect seismic motion |
|
Sensing chips |
Silicon chip that senses a physical quantity. Colibrys manufactures electromechanical chips that combine mechanical and electrical functions. |
|
Silicon micromachining |
Technology to manufacture micro-electro-mechanical components using processes similar as those used in Microelectronics chip manufacturing. Micromachining is broadly divided in 3 families: - Bulk micromachining where devices are etched with thickness of the full silicon wafer - Surface micromachining where devices are structured in thin films only a few - Galvanic micromachining where metallic devices of a few 10’s of micron thickness are |
|
Silicon wafer |
A wafer is a thin slice of semiconducting material, such as a silicon crystal, upon which microcircuits or MEMS devices are constructed by doping (for example, diffusion or ion implantation), chemical etching, and deposition of various materials. |
|
SMH Structural health monitoring |
Structural health monitoring (SHM) is an upcomingtechnology in civil, mechanical and aerospace engineering to continuously monitor the properties of structures to obtain information on the integrity and health of that structure. |
|
Strong motion sensors |
Accelerometers used to measure the motion associated with nearby earthquakes |
|
S-wave |
Shear Wave (S-wave): Also known as converted wave and transverse, a shear wave is a seismic wave that moves rocks from side to side as it moves through them. |
|
System in a package |
Subsystem combining different components in a single package |
|
Temperature sensitivity |
Sensitivity of a given performance characteristic (typically scale factor, bias, or axis misalignment) to operating temperature, specified as worst case value over the full operating temperature range. Expressed as the change of the characteristic per degree of temperature change; a signed quantity, typically in ppm/°C for scale factor and g/°C for bias. This figure is useful for predicting maximum scale factor error with temperature, as a variable when modeling is not accomplished |
|
Tilt sensor |
Accelerometer used to measure the inclination |
|
UMS |
Unattended measurement system |
|
Variable capacitance accelerometer |
Accelerometer using capacitive detection of the motion of a proof mass suspended by springs. |
|
Vibration sensor |
Acceleration sensor with a large bandwidth used to measure vibration |
|
Wafer fab |
Manufacturing infrastructure to process wafers |
|
Wafer level packaging |
Technology where electromechanical structures are sealed on the level of the silicon MEMS chip. Colibrys uses a specific wafer level packaging technology to manufacture vacuum sealed accelerometer chips |
|
Weak motion sensors |
Accelerometers used to measure weak seismic motion originating from earthquakes at large distances |