In security technology, the ability to check items of baggage or to monitor hazard areas is playing an increasingly important role. Sea ports and airports use inspection and security systems such as container scanners, cargo scanners, and baggage scanners to screen and inspect vehicles, freight, and baggage. Accidents in nuclear reactors have led to increased demand for radiation measuring devices to detect radioactive contamination. Other applications for our silicon radiation sensors are X-ray fluorescence spectrometers and equipment for non-destructive material testing.
First Sensor offers a range of photodiodes and sensor systems for measuring ionizing radiation for devices used in inspection and security technology, process monitoring, material analysis and material testing. Alpha, beta, gamma, and X-ray radiation can be detected with silicon PIN photodiodes either directly via the absorption in the crystal lattice or indirectly via the measurement of the luminescence radiation of a scintillation crystal. Scintillators convert the high-energy, ionizing radiation into visible light, which is then measured by highly sensitive photodiodes. First Sensor's Series X uses CsI:TI crystals, which achieve a high level of efficiency during the conversion of radiation and emit in the green wavelength range. Silicon absorbs gamma radiation very effectively in the energy range from 1 to 40 keV. With a scintillation crystal, higher radiation energies of up to 1 MeV can also be reliably detected indirectly by silicon photodiodes. In this case, the crystal protects the photodiode from direct high-energy radiation.
First Sensor offers optimized silicon PIN photodiodes, which form wide, fully depleted space-charge regions even at low reverse voltages in order to guarantee the maximum absorption of radiation. The fully depleted PIN photodiodes from Series 7 enable very large absorptions volumes and extremely low dark currents.