Speaker
Description
The MiniCACTUS prototypes are large fill-factor monolithic demonstrator sensors optimised for timing measurement of charged particles in future high-energy physics large-scale timing detectors. They are designed in 150 nm LFoundry HV-CMOS process and produced on high resistivity p-type silicon substrates with a deep n-well acting as collecting electrode.
The MiniCACTUSV2 is the latest iteration of the chip featuring pixel structures with different implant sizes ranging from $1.0\times1.0$ $mm^{2}$ down to 50 × 50 µm with dedicated analog front-ends and discriminators implemented at the column level.
The chips are thinned down to 150, 175 and 200 µm active thickness and processed for backside biasing.
Detection efficiency and time resolution of these prototypes have been studied in testbeam experiments at SPS CERN using high energy pion beams. Best performance has been observed for the $0.5\times0.5$ $mm^{2}$ structures reaching less than 50 ps resolution when operated with bias voltage above 300 V.
While these results have been obtained on pixels without gain layer, first prototypes of pixel diodes with intrinsic gain have been recently produced at LFoundry on both 150 µm high resistivity substrates and 30 µm epitaxial active silicon layers.
In this presentation, we provide an overview of the MiniCACTUSV2 testbeam characterisation results, along with the initial characterisation of the gain-layer diodes.