Report on the X-ray efficiency and time response of a 1 cm2 reach through avalanche diode

We report the time response and efficiency of a 1 cm2 reach through avalanche photodiode used for direct detection of X-rays. The efficiency varies from ∼ 70% at 8 keV to ∼ 15% at 16 keV, consistent with an active thickness of more than 90 μm of silicon. The time resolution, full width-at-half-maximum, is 0.8 ns.