Terasense has developed an original patent-protected technology for making a new type of semiconductor detectors for sub-THz rays operating at room temperatures. The detectors can be combined into a compact and rather inexpensive sensor array (similar to CCD/CMOS sensors in a photo camera). The Company is developing imaging applications for THz and sub-THz frequency ranges based on its sensors.
Terahertz imaging cameras
- Operates at frequencies (0.05 - 0.7 THz), where most common materials are transparent
- Different models are available: 256 pixels; 1024 pixels; 4096 pixels - to accomodate any budget
The detectors are fabricated from GaAs high-mobility heterostructure in the standard semiconductor cycle using conventional optical lithography. The imaging sensor is manufactured on a single wafer. That process ensures high homogeneity and reproducibility of the plasmonic detector parameters (pixel-to-pixel deviation responsivity is within 20-percent range). Each unit detector proved to have room-temperature responsivity up to 50 kV/W with read-out circuitry and noise equivalent power 1 nW/Hz^0.5 in the frequency range 10 GHz – 1 THz. The detection mechanism is based on transformation of incident THz radiation into two-dimensional electron system (2DES) plasma oscillation. Plasma wave is then rectified on the inhomogeneity of 2DES electron density in the defect region.
Visit Terasense's website for more information on their Terahertz Imaging cameras
High speed linear THz camera
- Image acquisition rate: 5 KHz (5000 fps)
- Scanning speed: up to 15m/sec (900m/min)
- Spectral range: 50 GHz – 0.7 THz
- Number of pixels (scalable): 256 x 1
- TeraFast® Viewer software
- Warranty period: 1.5 years
- Easily integrated into production process
High Speed Linear THz camera features both, unprecedented imaging speed of 5000 frames per second and ease of integration into any industrial process. Its ultrafast linear sensor array is built to satisfy the needs in Non- Destructive Testing (NDT) and Quality Control (QC) for many industrial applications employing high speed conveyors belts. This product fits most conveyors with a belt speed up to 15 m/s.
Terahertz generators (IMPATT diodes)
- 80 - 120 GHz frequency range
- Typical output power 10 mW
- Low cost and compact
An IMPATT diode (IMPact ionization Avalanche Transit-Time) is a high-power diode used in microwave electronics and sub-THz devices. They operate at frequency range 3 - 400 GHz. Main advantage is their high-power capability and small size. The IMPATT diode operates over a narrow frequency band, and diode internal dimensions must correlate with the desired operating frequency.
TeraSense series of IMPATT diodes are silicon double drift diodes with a 0.6 um transit region, mounted on copper heat sink. The layers in double-drift diodes are: a heavily doped (p+)-region, a moderately doped pregion, a moderately doped n-region, and a heavily doped (n+)-region. The (p+)- and (n+)- regions allow ohmic electrical contacts to be made to the external circuit. The device relies on negative resistance to generate and sustain an oscillation.
Ultrafast Terahertz detectors
- Response time: 150 ps
- Spectral Range: 50 GHz - 1.0 THz
- Responsivity (typical): 1 V/W
- Noise Equivalent Power : 1 nW/√Hz
- Sensitive area: 3 x 3.5 mm
- No power supply needed
- Compact size: 23 x 29 x 6.5 mm
Ultrafast detectors by TeraSense consistently demonstrate response time of less than 150 ps. This was confirmed by direct observation of its impulse response function. The detector was excited by 200 nJ 1 ps laser pulse with a broad spectrum ranging from 0.1 to 3 THz, and its response was recorded by a high speed oscilloscope. The response function shows rise and fall times of 150 ps limited by the oscilloscope 4 GHz bandwidth.
Visit Teresense's webisite for more information on their THz Detectors