Equivalent Noise Charge of Monolithic Active Pixel Sensors for Use in Charged Particle Detection

The Equivalent Noise Charge (ENC) of Monolithic Active Pixel Sensors has been determined using an analytical approach. The ENC is an important characteristic when these sensors are used for charged particle detection as it determines the Signal to Noise ratio. This paper gives the dominant contributions to the temporal noise as a function of an observation time directly related to the clocking frequency of the pixel array. Measured data made on MIMOSA8 array confirms the validity of the approach. In addition both theoretical computation and experimental data show that the residual ENC is of the order of 10 e- and can be further reduced.