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arXiv · 1906.09207

Hybrid CMOS detectors for the Lynx x-ray surveyor high definition x-ray imager

Samuel V. Hull·Abraham D. Falcone·Evan Bray·Mitchell Wages·Maria McQuaide·David N. Burrows
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Abstract

X-ray hybrid CMOS detectors (HCDs) are a promising candidate for future x-ray missions requiring high throughput and fine angular resolution along with large field-of-view, such as the high-definition x-ray imager (HDXI) instrument on the Lynx x-ray surveyor mission concept. These devices offer fast readout capability, low power consumption, and radiation hardness while maintaining high detection efficiency from 0.2 to 10 keV. In addition, x-ray hybrid CMOS sensors may be fabricated with small pixel sizes to accommodate high-resolution optics and have shown great improvements in recent years in noise and spectral resolution performance. In particular, 12.5-{\mu}m pitch prototype devices that include in-pixel correlated double sampling capability and crosstalk eliminating capacitive transimpedance amplifiers, have been fabricated and tested. These detectors have achieved read noise as low as 5.4 e-, and we measure the best energy resolution to be 148 eV (2.5%) at 5.9 keV and 78 eV (14.9%) at 0.53 keV. We will describe the characterization of these prototype small-pixel x-ray HCDs, and we will discuss their applicability to the HDXI instrument on Lynx.

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Samuel V. Hull, Abraham D. Falcone, Evan Bray, Mitchell Wages, Maria McQuaide, David N. Burrows. 2019-06-21. Hybrid CMOS detectors for the Lynx x-ray surveyor high definition x-ray imager. https://doi.org/10.1117/1.jatis.5.2.021018

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