  A new generation of Monolithic Active Pixel Sensors (MAPS), produced in a 65
nm CMOS imaging process, promises higher densities of on-chip circuits and, for
a given pixel size, more sophisticated in-pixel logic compared to larger
feature size processes. MAPS are a cost-effective alternative to hybrid pixel
sensors since flip-chip bonding is not required. In addition, they allow for
significant reductions of the material budget of detector systems, due to the
smaller physical thicknesses of the active sensor and the absence of a separate
readout chip. The TANGERINE project develops a sensor suitable for future Higgs
factories as well as for a beam telescope to be used at beam-test facilities.
The sensors will have small collection electrodes (order of $\mu$m) to maximize
the signal-to-noise ratio, which makes it possible to minimize power
dissipation in the circuitry. The first batch of test chips, featuring full
front-end amplifiers with Krummenacher feedback, was produced and tested at the
Mainzer Mikrotron (MAMI) at the end of 2021. MAMI provides an electron beam
with currents up to 100 $\mu$A and an energy of 855 MeV. The analog output
signal of the test chips was recorded with a high bandwidth oscilloscope and
used to study the charge-sensitive amplifier of the chips in terms of waveform
analysis. A beam telescope was used as a reference system to allow for
track-based analysis of the recorded data.
