A fast monolithic active pixel sensor with pixel-level reset noise suppression and binary outputs for charged particle detection

In order to develop precision vertex detectors for the future linear collider, fast monolithic active pixelsensors are studied. A standard CMOS 0.25 mum digital process is used to design a test chip which includes different pixeltypes, column-level discriminators, and a fully programmable digital sequencer. In- pixelamplification is implemented together with double sampling. Different charge-to-voltage conversion factorswere obtained using amplifiers with different gains or diode sizes. Pixelarchitectures with dc and ac coupling to charge sensing element were proposed. Hits from conversion of 55 Fe photons were recorded for the dc-coupled and ac-coupled pixelversions. Double sampling is functional and allows almost a complete cancellation of fixed pattern noise