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 pixel sensors are studied. A standard CMOS 0.25 /spl mu/m digital process is used to design a test chip which includes different pixel types, column-level discriminators, and a fully programmable digital sequencer. In-pixel amplification is implemented together with double sampling. Different charge-to-voltage conversion factors were obtained using amplifiers with different gains or diode sizes. Pixel architectures with dc and ac coupling to charge sensing element were proposed. Hits from conversion of /sup 55/Fe photons were recorded for the dc-coupled and ac-coupled pixel versions. Double sampling is functional and allows almost a complete cancellation of fixed pattern noise.