Speaker
Fergus Wilson
(STFC - Rutherford Appleton Lab. (GB))
Description
We report on the status and performance of the CMOS Monolithic Active Pixel Sensor (MAPS) Cherwell 1 and 2 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 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 is a prototype candidate sensor to be used in the upgrade of the ALICE Inner Tracker System at the LHC. It has three variants of a 128x128 pixel array on 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.
Summary
Performance of two prototype CMOS MAPS sensors.
Primary author
Fergus Wilson
(STFC - Rutherford Appleton Lab. (GB))
Co-authors
Adrian Bevan
(University of London (GB))
Jaap Velthuis
Roy Crawford Lemmon
(STFC Daresbury Laboratory (GB))
renato turchetta
(ral-stfc)
