In this paper, we report on the radiation resistance of 50-micron thick Low Gain Avalanche Diodes (LGAD) manufactured at the Fondazione Bruno Kessler (FBK) employing different dopings in the gain layer.LGADs with a gain layer made of Boron, Boron lowdiffusion, Gallium, Carbonated Boron and Carbonated Gallium have been designed and successfully produced at FBK. These sensors have been exposed to neutron fluences up to φ n ∼ 3 · 10 16 n/cm 2 and to proton fluences up to φ p ∼ 9 · 10 15 p/cm 2 to test their radiation resistance. The experimental results show that Gallium-doped LGAD are more heavily affected by the initial acceptor removal mechanism than those doped with Boron, while the addition of Carbon reduces this effect both for Gallium and Boron doping. The Boron low-diffusion gain layer shows a higher radiation resistance than that of standard Boron implant, indicating a dependence of the initial acceptor removal mechanism upon the implant density.The LGAD design evolves the standard silicon sensors design by incorporating low, controlled gain [1] in the signal formation mechanism. The overarching idea is to manufacture silicon detectors with signals large enough to assure excellent timing performance while maintaining almost unchanged levels of noise [2].Charge multiplication in silicon sensors happens when the charge carriers (electrons and holes) are in electric fields of the order of E ∼ 300 kV/cm [3]. Under this condition, the electrons (and to less extent the holes) acquire sufficient kinetic energy to generate additional e/h pairs by impact ionization. Field values of ∼300 kV/cm can be obtained by implanting an appropriate acceptor (or donor) charge density ρ A (of the order ρ A ∼

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The solution-processability of organic photodetectors allows a straightforward combination with other materials, including inorganic ones, without increasing cost and process complexity significantly compared with conventional crystalline semiconductors. Although the optoelectronic performance of these organic devices does not outmatch their inorganic counterparts, there are certain applications exploiting the benefit of the solution-processability. Here we demonstrate that the small pixel fill factor of present complementary metal oxide semiconductor-imagers, decreasing the light sensitivity, can be increased up to 100% by replacing silicon photodiodes with an organic photoactive layer deposited with a simple low-cost spray-coating process. By performing a full optoelectronic characterization on this first solution-processable hybrid complementary metal oxide semiconductor-imager, including the first reported observation of different noise types in organic photodiodes, we demonstrate the suitability of this novel device for imaging. Furthermore, by integrating monolithically different organic materials to the chip, we show the cost-effective portability of the hybrid concept to different wavelength regions.

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