FastIC: a fast integrated circuit for the readout of high performance detectors

This work presents the 8-channel FastIC ASIC developed in CMOS 65 nm technology suitable for the readout of positive and negative polarity sensors in high energy physics experiments, Cherenkov detectors and time-of-flight systems. The front-end can be configured to perform analog summation of up to 4 single-ended channels before discrimination in view of improving time resolution when segmenting a SiPM. The outputs encode the time-of-arrival information and linear energy measurement which captures the peak amplitude of the input signal in the 5 µA–25 mA input peak current range. Power consumption of the ASIC is 12 mW/ch with default settings. Measurements of single photon time resolution with a red-light laser source and a HPK SiPM S13360-3050CS are ≈140 ps FWHM

Multimodal simulation of large area silicon photomultipliers for time resolution optimization

The Silicon Photomultiplier (SiPM) sensor is replacing the extensive use of the Photomultiplier Tube (PMT) in fast timing applications. These photo-sensors can be applied in different fields such as medical imaging systems like Positron Emission Tomography (PET), LIDAR technologies or High Energy Physics (HEP) experiments. More specific, Time-of-Flight PET (ToF-PET) requires further developments to achieve a Coincidence Time Resolution (CTR) of 10ps, this enabling the real time reconstruction and in vivo molecular examination. The most recent state-of-the-art ToF-PET systems can reach 200 ps in CTR. Lowering this value will require a cross-optimization of the scintillator crystal, the sensor and the electronics at the same time. These three elements optimization will be the key to boost the timing resolution of the complete system. The aim of this work is to provide a simulation framework that enables this cross-optimization of the PET system taking into consideration the photon physics interaction in the scintillator crystal, the sensor response (size, dead area, capacitance) and the readout electronics behavior (input impedance, noise, bandwidth). This framework has allowed us to study a new promising approach that helps reducing the CTR parameter by segmenting a large area SiPM into ?m?smaller SiPMs and then, summing the signals to recover all the signal spread along these smaller sensors. A 15% improvement on time resolution is expected by segmenting a 4 mm x 4 mm single sensor into 9 sensors of 1.3 mm x 1.3 mm with respect to the case where no segmentation is applied. The Silicon Photomultiplier (SiPM) sensor is replacing the extensive use of the Photomultiplier Tube (PMT) in fast timing applications. These photo-sensors can be applied in different fields such as medical imaging systems like Positron Emission Tomography (PET), LIDAR technologies or High Energy Physics (HEP) experiments. More specific, Time-of-Flight PET (ToF-PET) requires further developments to achieve a Coincidence Time Resolution (CTR) of 10ps, this enabling the real time reconstruction and in vivo molecular examination. The most recent state-of-the-art ToF-PET systems can reach 200 ps in CTR. Lowering this value will require a cross-optimization of the scintillator crystal, the sensor and the electronics at the same time. These three elements optimization will be the key to boost the timing resolution of the complete system. The aim of this work is to provide a simulation framework that enables this cross-optimization of the PET system taking into consideration the photon physics interaction in the scintillator crystal, the sensor response (size, dead area, capacitance) and the readout electronics behavior (input impedance, noise, bandwidth). This framework has allowed us to study a new promising approach that helps reducing the CTR parameter by segmenting a large area SiPM into ?m?smaller SiPMs and then, summing the signals to recover all the signal spread along these smaller sensors. A 15% improvement on time resolution is expected by segmenting a 4 mm x 4 mm single sensor into 9 sensors of 1.3 mm x 1.3 mm with respect to the case where no segmentation is applied