Speaker
Dr
Razmik Mirzoyan
(Max-Planck-Institute for Physics)
Description
The collaboration MEPhI-Max Plank Institute for Physics (Munich)for about ten years is developing SiPMs for the needs of the MAGIC and EUSO astro-particle physics experiments. The aim was to develop UV sensitive very high Photon Detection Efficiency (PDE) devices, substantially exceeding that of the classical photo multiplier tubes (PMT). For achieving very high PDE one needs to operate SiPM under the highest Geiger efficiency, i.e. one needs to apply a high over-voltage to the sensors. This means operating SiPM under very high gain. As a consequence one will have a very high-level of cross-talk (X-talk). We simulated and tested several recipes of X-talk suppression in many experimental batches of devices. Together with isolating trenches and the second p-n junction, creating a potential barrier against the charge from the bulk, also special implantation profiles and layers were used for suppressing the adverse effect. We have produced several tens of wafers of 18 different variations of SiPM. Below we report on the excellent properties of some selected types of SiPM of 1x1mm² and of 3x3mm² sizes. The 1x1mm² SiPMs show a PDE of ~ 45 % in the near UV - blue wavelength range. The cross-talk level is below 3.5 % and the dark rate is below 800 kHz at room temperature. Simultaneously we have measured excellent timing properties (see Fig.3), a time resolution of ~ 200ps has been measured for 3x3 mm² SiPMs. One of the most outstanding features of the novel devices is the extremely low level of temperature sensitivity of the gain, amounting to 0.5 %/°C (Fig.2). This is more than one order of magnitude lower compared to existing commercial devices. In this report we want to dwell on the measured parameter values for different type sensors, that are on the way of becoming ideal low light level sensor.
Author
Dr
Razmik Mirzoyan
(Max-Planck-Institute for Physics)
Co-authors
Prof.
Boris Dolgoshein
(Moscow Engineering and Physics Institute)
Elena Popova
(Moscow Engineering and Physics Institute)
Prof.
Masahiro Teshima
(Max-Planck-Institute for Physics)
Pavel Buzhan
(Moscow Engineering and Physics Institute)
