Marcello Borri (STFC Daresbury Laboratory (GB))
We report on the status and performance of the CMOS Monolithic Active Pixel Sensor (MAPS) Cherwell 1, 2 and 3 sensors for the detection of charged particles in vertexing, tracking, and calorimetry applications. Cherwell is a 4-T CMOS sensor in 180 nm technology on a 12um epitaxial substrate with low-noise, low-power, in-pixel correlated double sampling, and high conversion gain. Cherwell 1 was developed for Linear Collider studies and consists of four arrays, two optimized for vertexing and tracking applications, and two for digital calorimetry applications. The vertexing arrangements have a matrix of 96x48 pixels with a pitch of 25 um. The “reference array” is readout on a rolling shutter base with a fine resolution 12-bit, single-slope column parallel ADC. The “strixel" array has the readout and ADC circuits embedded in the space between the pixel diodes. The two sections for calorimetry have a matrix of 96x48 pixels with 25 um pitch and 48x24 pixels with 50 um pitch, respectively. Additional circuitry is added to provide charge summing of 2x2 pixels during readout. Cherwell 2 and 3 are prototype candidate sensors developed for the upgrade of the ALICE Inner Tracker System at the LHC. A number of variants have been produced on an 128x128 pixel array with a 20um pitch using the strixel technology. We report on the characterisation and performance of the prototypes, on the test bench, and at the test beam.
Fergus Wilson (STFC - Rutherford Appleton Lab. (GB))
Adrian Bevan (University of London (GB)) Gianluca Inguglia (Queen Mary University of London) Ian Lazarus (STFC Daresbury Lab) Jaap Velthuis Jamie Crooks (STFC Rutherford Appleton Laboratory) John Morris (University of London (GB)) Marcello Borri (STFC Daresbury Laboratory (GB)) Marian Krivda (University of Birmingham (GB)) Renato Turchetta (STFC - Rutherford Appleton Lab. (GB)) Roy Crawford Lemmon (STFC Daresbury Laboratory (GB)) Zhige Zhang (STFC - Science & Technology Facilities Council (GB))