UCF researchers have developed a photodetector able to operate at room temperature and measure spectral ranges including microwave, THz, SWIR, MWIR, and LWIR while maintaining image detail. Current commercial photodetectors are limited by the sensor’s spectral responsivity, requiring multiple sensors or unique configurations to image and sense a wide spectral range. A new nanostructured sensor design fundamentally improves responsivity while providing a simpler and more cost-effective approach than existing products.
Formed on the surface of a silicon wafer by laser processing, 3D nanostructures enhance collection efficiency while enabling multi-wavelength absorption via varyingly doped band sections, each contributing to the total spectrum detectable by the sensor. This high detectivity is coupled with high sensitivity, represented by the sensor’s low noise equivalent temperature difference (NETD), providing high signal-to-noise data for uses including: military applications, nondestructive testing, process control in manufacturing, and biomedical imaging.
The 3D sensor structure is fabricated by the use of laser-assisted deposition (LAD) and laser-assisted dopant incorporation (LADI). The laser processing creates an array of conical, pyramidal, or other 3D shapes to enhance surface area and responsivity. The sensor detects a range of wavelengths as specified by means of user-customizable magnetic doping in ring-like sections along the vertical axis of the structure. An array of structures with various dopant materials and concentrations can operate over a wide range of wavelengths and comprise a focal plane array. The fundamental nature of the sensor’s 3D nanostructure and magnetic dopant rings extends beyond photodetection to detection using polarization, static magnetic field detection, and gas and pressure detection featuring passive or active sensing modes.
- Operates at room temperature: 25°C
- Broadband detection: THz, SWIR, MWIR, LWIR
- High detectivity and sensitivity
- Multifunction: Detects polarization, static magnetic fields, gas, pressure
- Optical readout
- Photon-trapping vertical structures can replace anti-reflection coating
- Biomedical imaging
- Military applications
- Nondestructive testing
- Manufacturing: process control