Monolithic pixel sensor with 25 µm × 35 µm pixel size and high time resolution implemented in 180 nm technology

A monolithic pixel sensor with small collection electrode and partially depleted sensor diode named HVMAPS25 has been implemented in the 180 nm technology of TSI semiconductors. The pixel size is 25 μm × 35 μm. The pixel electronics contains a fast and low power charge sensitive amplifier, a comparator, a threshold tuning DAC and a digital block that measures the arrival time of the hit with 10 bit resolution and the signal amplitude (time over threshold) with 6 bit resolution. A deep p-well has been used for isolation of the pixel electronics from the sensor substrate. The building blocks of the chip, simulations and the measurement results will be presented.