Picosecond Avalanche Detector -- working principle and gain measurement with a proof-of-concept prototype

L. Paolozzi; M. Munker; R. Cardella; M. Milanesio; Y. Gurimskaya; F. Martinelli; A. Picardi; H. Rücker; A. Trusch; P. Valerio; F. Cadoux; R. Cardarelli; S. Débieux; Y. Favre; C. A. Fenoglio; D. Ferrere; S. Gonzalez-Sevilla; R. Kotitsa; C. Magliocca; T. Moretti; M. Nessi; A. Pizarro Medina; J. Sabater Iglesias; J. Saidi; M. Vicente Barreto Pinto; S. Zambito; G. Iacobucci

arXiv · 2206.07952

Picosecond Avalanche Detector -- working principle and gain measurement with a proof-of-concept prototype

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Abstract

The Picosecond Avalanche Detector is a multi-junction silicon pixel detector based on a $\mathrm{(NP)_{drift}(NP)_{gain}}$ structure, devised to enable charged-particle tracking with high spatial resolution and picosecond time-stamp capability. It uses a continuous junction deep inside the sensor volume to amplify the primary charge produced by ionizing radiation in a thin absorption layer. The signal is then induced by the secondary charges moving inside a thicker drift region. A proof-of-concept monolithic prototype, consisting of a matrix of hexagonal pixels with 100 $\mu$m pitch, has been produced using the 130 nm SiGe BiCMOS process by IHP microelectronics. Measurements on probe station and with a $^{55}$Fe X-ray source show that the prototype is functional and displays avalanche gain up to a maximum electron gain of 23. A study of the avalanche characteristics, corroborated by TCAD simulations, indicates that space-charge effects due to the large primary charge produced by the conversion of X-rays from the $^{55}$Fe source limits the effective gain.

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L. Paolozzi, M. Munker, R. Cardella, M. Milanesio, Y. Gurimskaya, F. Martinelli, A. Picardi, H. Rücker, A. Trusch, P. Valerio, F. Cadoux, R. Cardarelli, S. Débieux, Y. Favre, C. A. Fenoglio, D. Ferrere, S. Gonzalez-Sevilla, R. Kotitsa, C. Magliocca, T. Moretti, M. Nessi, A. Pizarro Medina, J. Sabater Iglesias, J. Saidi, M. Vicente Barreto Pinto, S. Zambito, G. Iacobucci. 2022-06-16. Picosecond Avalanche Detector -- working principle and gain measurement with a proof-of-concept prototype. https://arxiv.org/abs/2206.07952

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