Design of Monolithic Bi-Layer High-Z PAL-Si Hard X-ray CMOS Image Sensors for Quantum Efficiency Enhancement

Journal Article · 27 August 2023 · Instruments

DOI: https://doi.org/10.3390/instruments7030024 · OSTI ID:1997277

Lee, Eldred; Larkin, Kevin D.; Yue, Xin; Wang, Zhehui ; Fossum, Eric R. ; Liu, Jifeng

This article experimentally investigates the inception of an innovative hard X-ray photon energy attenuation layer (PAL) to advance high-energy X-ray detection (20–50 keV). A bi-layer design with a thin film high-Z PAL on the top and Si image sensor on the bottom has previously demon-strated quantum yield enhancement via computational methods by the principle of photon energy down conversion (PEDC), where high-energy X-ray photon energies are attenuated via inelastic scattering down to ≤10 keV, which is suitable for efficient photoelectric absorption by Si. Quantum yield enhancement has been experimentally confirmed via a preliminary demonstration using PAL-integrated Si-based CMOS image sensors (Si CIS). Furthermore, substituting the high-Z PAL with a lower-Z material—Sn—and alternatively coupling it with a conventional scintillator ma-terial—Lutetium-yttrium oxyorthosilicate (LYSO)—have been compared to demonstrate the most prominent efficacy of monolithic integration of high-Z PAL on Si CIS to detect hard X-rays, paving the way for next-generation high-energy X-ray detection methods.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE National Nuclear Security Administration (NNSA), Office of Defense Programs (DP)
• Grant/Contract Number: 89233218CNA000001; NA0003864; NA0003960
• OSTI ID: 1997277
• Report Number(s): LA-UR--24-23399; PII: instruments7030024
• Journal Information: Instruments, Journal Name: Instruments Journal Issue: 3 Vol. 7; ISSN 2410-390X; ISSN INSTCO
• Publisher: MDPI AGCopyright Statement
• Country of Publication: Switzerland
• Language: English