On the Single-Photon-Counting (SPC) modes of imaging using an XFEL source

Abstract

The requirements to achieve high detection efficiency (above 50%) and gigahertz (GHz) frame rate for the proposed 42-keV X-ray free-electron laser (XFEL) at Los Alamos are summarized. Direct detection scenarios using C (diamond), Si, Ge and GaAs semiconductor sensors are analyzed. Single-photon counting (SPC) mode and weak SPC mode using Si can potentially meet the efficiency and frame rate requirements and be useful to both photoelectric absorption and Compton physics as the photon energy increases. Multilayer three-dimensional (3D) detector architecture, as a possible means to realize SPC modes, is compared with the widely used twodimensional (2D) hybrid planar electrode structure and 3D deeply entrenched electrode architecture. Demonstration of thin film cameras less than 100-µm thick with onboard thin ASICs could be an initial step to realize multilayer 3D detectors and SPC modes for XFELs.

Billion-pixel x-ray camera (BiPC-X)

“…Using as building blocks the CIS with millions of pixels (MP), a BiPC-X can be constructed through multi-layer stacking and tiling [2][3][4] . Several possible configurations are illustrated as D 1 , D 2 and D 3 in Fig.…”

“…There are several approaches to overcome the low detection efficiency of the visiblelight CIS for X-ray photon detection. A multi-layer CIS architecture has been described recently 2,3 , and validated with initial X-ray experiments at the Argonne a) Contributed paper to the Proceedings of the 23rd Topical Conference on High-Temperature Plasma Diagnostics, Santa Fe, NM, USA, May 31 -June 4, 2020. Rescheduled online, Dec. 14-17, 2020.…”

A new approach to achieving high granularity for silicon diode detectors with impact ionization gain

“…This limits the granularity of practical sensors to the 1 mm scale, since a finer granularity would dramatically decrease the sensor active area. However, to make use of LGAD technology to fully exploit the capabilities of future accelerator facilities -to accomplish "4D tracking" for colliding beam detectors [17] or X-ray imaging at next-generation light sources [14] -granularity of better than 100 µm will be required.…”

“…As a result, the granularity of the LGAD sensors under development for use at the HL-LHC is limited to the millimeter scale. Although this degree of granularity is acceptable for HL-LHC applications, many possible future applications of LGADs, such as four-dimensional tracking at future colliding beam facilities, X-ray imaging, and medical physics applications, will require granularity at the tens-of-micron scale [14].…”

Monte Carlo Modeling and Design of Photon Energy Attenuation Layers for >10× Quantum Yield Enhancement in Si-Based Hard X-ray Detectors

“…Since the discovery of X-rays by Roentgen, the continuous expansion of X-ray technology has transformed our society from materials science to biomedical applications. However, the capability gap for efficient and direct detection of high-energy X-ray photons in the 20-50keV range and beyond is challenging, which will prevent further advancements in rising fields of technology such as the generic platform of X-ray imaging sensor technology, quantum computing, and the next generation of synchrotron light source facilities [1][2][3][4][5]. Scintillator-based methods are widely used in these types of facilities and high-energy X-ray detection technologies; however, they have major limitations such as decay time response and light yield [6,7].…”