Functional Near Infrared Spectroscopy (fNIRS) uses near infrared sources and detectors to measure changes in
absorption due to neurovascular dynamics in response to brain activation. The use of Silicon Photomultipliers (SiPMs) in
a fNIRS system has been estimated potentially able to increase the spatial resolution. Dedicated SiPM sensors have been
designed and fabricated by using an optimized process. Electrical and optical characterizations are presented. The design
and implementation of a portable fNIRS embedded system, hosting up to 64 IR-LED sources and 128 SiPM sensors, has
been carried out. The system has been based on a scalable architecture whose elementary leaf is a flexible board with 16
SiPMs and 4 couples of LEDs each operating at two wavelengths. An ARM based microcontroller has been joined with a
multiplexing interface, able to control power supply for the LEDs and collect data from the SiPMs in a time-sharing
fashion and with configurable temporal slots. The system will be validated by using a phantom made by materials of
different scattering and absorption indices layered to mimic a human head. A preliminary characterization of the optical
properties of the single material composing the phantom has been performed using the SiPM in the diffuse radial
reflectance measurement technique. The first obtained results confirm the high sensitivity of such kind of detector in the
detection of weak light signal even at large distance between the light source and the detector.
We report on the design and the electro-optical characterization of a novel class of 4H-SiC vertical Schottky UV
detectors, based on the pinch-off surface effect and obtained employing Ni2Si interdigitated strips. We have measured, in
dark conditions, the forward and reverse I–V characteristics as a function of the temperature and the C–V characteristics.
Responsivity measurements of the devices, as a function of the wavelength (in the 200 – 400 nm range), of the package
temperature and of the applied reverse bias are reported. We compared devices featured by different strip pitch size, and
found that the 10 μm device pitch exhibits the best results, being the best compromise in terms of full depletion and
space-strip width ratio.