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arXiv · 2406.06472

Multi-Amplifier Sensing Charge-coupled Devices for Next Generation Spectroscopy

Abstract

We present characterization results and performance of a prototype Multiple-Amplifier Sensing (MAS) silicon charge-coupled device (CCD) sensor with 16 channels potentially suitable for faint object astronomical spectroscopy and low-signal, photon-limited imaging. The MAS CCD is designed to reach sub-electron readout noise by repeatedly measuring charge through a line of amplifiers during the serial transfer shifts. Using synchronized readout electronics based on the DESI CCD controller, we report a read noise of 1.03 e$^-$ rms/pix at a speed of 26 $\mu$s/pix with a single-sample readout scheme where charge in a pixel is measured only once for each output stage. At these operating parameters, we find the amplifier-to-amplifier charge transfer efficiency (ACTE) to be $>0.9995$ at low counts for all amplifiers but one for which the ACTE is 0.997. This charge transfer efficiency falls above 50,000 electrons for the read-noise optimized voltage configuration we chose for the serial clocks and gates. The amplifier linearity across a broad dynamic range from $\sim$300 to 35,000 e$^-$ was also measured to be $\pm 2.5\%$. We describe key operating parameters to optimize on these characteristics and describe the specific applications for which the MAS CCD may be a suitable detector candidate.

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Kenneth W. Lin, Armin Karcher, Julien Guy, Stephen E. Holland, William F. Kolbe, Peter E. Nugent, Alex Drlica-Wagner, Ana M. Botti, Javier Tiffenberg. 2024-06-10. Multi-Amplifier Sensing Charge-coupled Devices for Next Generation Spectroscopy. https://doi.org/10.1088/1538-3873%2Fad716c

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