Characterization of Fully Depleted CMOS Active Pixel Sensors on High Resistivity Substrates for Use in a High Radiation Environment

Abstract: Depleted CMOS active sensors (DMAPS) are being developed for high-energy particle physics experiments in high radiation environments, such as in the ATLAS High Luminosity Large Hadron Collider (HL-LHC). Since charge collection by drift is mandatory for harsh radiation environment, the application of high bias voltage to high resistive sensor material is needed. In this work, a prototype of a DMAPS was fabricated in a 150nm CMOS process on a substrate with a resistivity of >2 k{\Omega}cm that was thinned to 100 {\mu}m. Full depletion occurs around 20V, which is far below the breakdown voltage of 110 V. A readout chip has been attached for fast triggered readout. Presented prototype also uses a concept of sub-pixel en/decoding three pixels of the prototype chip are readout by one pixel of the readout chip. Since radiation tolerance is one of the largest concerns in DMAPS, the CCPD_LF chip has been irradiated with X-rays and neutrons up to a total ionization dose of 50 Mrad and a fluence of 10E15neq/cm2, respectively.