Detector thickness effects on nanosecond-gated imager response

Abstract

Hybrid CMOS multi-frame imagers with exposure times down to ∼2 ns have made significant impacts in high energy density physics and inertial confinement fusion research. The detector thickness is a key parameter in both detector quantum efficiency and temporal response. The Icarus hybrid CMOS imager has been fabricated with Si detector thicknesses of 8, 25, and 100 µm. The temporal response of imaging sensors with exposure time down to 2 ns has been examined and compared to directly measured photodiode current. The 100-μm thick variant displays extended features related to charge carrier collection and is more susceptible to field collapse. We also demonstrate charge collection time effects on spatial response.

Characterization suite of a 1 ns, multi-frame hybridized CMOS imager for the ultra-fast x-ray imager program

“…Since each data point in a gate profile is derived from a different sensor trigger event and the input is a near impulse response for the photodiode, effects that vary for each trigger event should be considered when applying this characterization technique for a specific application. These effects include shot-to-shot jitter, thermal drift, pixel trigger skew [2], the impulse response of the diode [3], as well as global effects that impact overall sensor performance.…”