A 7.2inch 5.5Mpixel 600mW SPAD X-Ray Detector with 116.7 dB Dynamic Range

• Published in: 2024 IEEE Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits) pp. 1 - 2
• Main Authors: Park, Byungchoul, Choi, Hyun-Seung, Jeong, Jinwoong, Cheon, Jimin, Lee, Myung-Jae, Chae, Youngcheol
• Format: Conference Proceeding
• Language: English
• Published: IEEE 16.06.2024
• Subjects: Power demand; Radiation detectors; Radiography; Single-photon avalanche diodes; Throughput; Very large scale integration; X-ray detectors
• ISSN: 2158-9682
• DOI: 10.1109/VLSITechnologyandCir46783.2024.10631519

This paper presents the first 7.2-inch wafer-level SPAD X-ray detector for radiography and industrial applications. A digital SPAD pixel achieves high SNR at low dose and wide DR. Large power consumption of the photon counting at high dose is effectively mitigated by using an extrapolation method, and the overflow flag of the photon counter is flexibly selected for further power reduction. High throughput is achieved with a pipelined readout chain of the pixel output. Implemented in a 65nm CMOS process, the detector consists of 3296\times 1680 pixels with a pixel pitch of 49.5\mu \mathrm{m} , corresponding to an area of 16.5\times 8.9\text{cm}^{2} , and consumes only 600mW at 13frames/s, while achieving a DR of 116.7dB. The global shutter operation delivers high-quality image without motion artifacts. Excellent radiation hardness of up to 10,000Gy is also achieved.