Time Resolution of a SiGe BiCMOS Monolithic Silicon Pixel Detector without Internal Gain Layer with a Femtosecond Laser

M. Milanesio; L. Paolozzi; T. Moretti; A. Latshaw; L. Bonacina; R. Cardella; T. Kugathasan; A. Picardi; M. Elviretti; H. Rücker; R. Cardarelli; L. Cecconi; C. A. Fenoglio; D. Ferrere; S. Gonzalez-Sevilla; L. Iodice; R. Kotitsa; C. Magliocca; M. Nessi; A. Pizarro-Medina; J. Sabater Iglesias; I. Semendyaev; J. Saidi; M. Vicente Barreto Pinto; S. Zambito; G. Iacobucci

arXiv · 2401.01229

Time Resolution of a SiGe BiCMOS Monolithic Silicon Pixel Detector without Internal Gain Layer with a Femtosecond Laser

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Abstract

The time resolution of the second monolithic silicon pixel prototype produced for the MONOLITH H2020 ERC Advanced project was studied using a femtosecond laser. The ASIC contains a matrix of hexagonal pixels with 100 {\mu}m pitch, readout by low-noise and very fast SiGe HBT frontend electronics. Silicon wafers with 50 {\mu}m thick epilayer with a resistivity of 350 {\Omega}cm were used to produce a fully depleted sensor. At the highest frontend power density tested of 2.7 W/cm2, the time resolution with the femtosecond laser pulses was found to be 45 ps for signals generated by 1200 electrons, and 3 ps in the case of 11k electrons, which corresponds approximately to 0.4 and 3.5 times the most probable value of the charge generated by a minimum-ionizing particle. The results were compared with testbeam data taken with the same prototype to evaluate the time jitter produced by the fluctuations of the charge collection.

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M. Milanesio, L. Paolozzi, T. Moretti, A. Latshaw, L. Bonacina, R. Cardella, T. Kugathasan, A. Picardi, M. Elviretti, H. Rücker, R. Cardarelli, L. Cecconi, C. A. Fenoglio, D. Ferrere, S. Gonzalez-Sevilla, L. Iodice, R. Kotitsa, C. Magliocca, M. Nessi, A. Pizarro-Medina, J. Sabater Iglesias, I. Semendyaev, J. Saidi, M. Vicente Barreto Pinto, S. Zambito, G. Iacobucci. 2024-01-02. Time Resolution of a SiGe BiCMOS Monolithic Silicon Pixel Detector without Internal Gain Layer with a Femtosecond Laser. https://arxiv.org/abs/2401.01229

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