Characterisation of AMS H35 HV-CMOS monolithic active pixel sensor prototypes for HEP applications

Abstract

A: Monolithic Active Pixel Sensors (MAPS) produced in High Voltage CMOS (HV-CMOS) technology are being considered for High Energy Physics applications due to the ease of production and the reduced costs. Such technology is especially appealing when large areas to be covered and material budget are concerned. This is the case of the outermost pixel layers of the future ATLAS tracking detector for the High Luminosity LHC. For experiments at hadron colliders, radiation hardness is a key requirement which is not fulfilled by standard CMOS sensor designs that collect charge by diffusion. This issue has been addressed by depleted active pixel sensors in which electronics are embedded into a large deep implantation ensuring uniform charge collection by drift. Very first small prototypes of hybrid depleted active pixel sensors have already shown a radiation hardness compatible with the ATLAS requirements. Nevertheless, to compete with the present hybrid solutions a further reduction in costs achievable by a fully monolithic design is desirable. The H35DEMO is a large electrode full reticle demonstrator chip produced in AMS 350 nm HV-CMOS technology by the collaboration . It includes two large monolithic pixel matrices which can be operated standalone. One of these two matrices was characterised at beam test before and after irradiation with protons and neutrons. Results demonstrated the feasibility of producing radiation hard large area fully monolithic pixel sensors in HV-CMOS technology. H35DEMO chips with a substrate resistivity of 200 Ωcm irradiated with neutrons showed a radiation hardness up to a fluence of 1 × 10 15 n eq /cm 2 with a hit efficiency of about 99 % and a noise occupancy lower than 10 −6 hits in a LHC bunch crossing of 25 ns at 150 V.

Sub-10 ps Minimum Ionizing Particle Detection With Geiger-Mode APDs

“…The beam profile measurement is reported in Figure 7. A good alignment between the two detectors has been achieved thanks to an HVCMOS telescope [26]. The two detectors were positioned at the center of the beam, where the intensity is the highest.…”

Sub-10 ps Minimum Ionizing Particle Detection with Geiger-Mode APDs

“…6. A good alignment between the two detectors has been achieved thanks to an HVCMOS telescope [25]. The two detectors were positioned at the center of the beam, where the intensity is the highest.…”