Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

The development of room-temperature Si infrared photodetectors, whose range of detection lies on the traditional telecommunication wavelengths around 1300 nm and 1550 nm, is of paramount importance for optical communications, integrated photonics, sensing and medical imaging applications [1]. The typical peak photoresponse of conventional Si photodetectors is between 700 and 900 nm, which is primarily limited by the 1.12 eV-Si band gap. However, such intrinsic material limitation can be overcome by introducing transition metals or chalcogens into the Si band gap at concentrations far above those obtained at equilibrium conditions [1, 2]. This new class of hyperdoped materials with a donor impurity band has been postulated as a viable route to extend the Si photoresponse at the infrared spectral region [3].
In this work, we report on the significant room-temperature photoresponse and performance at the two primary telecommunication wavelengths as exhibited by hyperdoped Si p-n photodiodes fabricated by Se implantation followed by millisecond flash lamp annealing (FLA). The FLA approach in the millisecond range allows for a solid-phase epitaxy that has been reported to be superior to liquid-phase epitaxy induced during pulsed laser annealing [2]. The success of our devices is primarily based on the high quality of the developed n-type hyperdoped material, which is single-phase single crystal with high electrical activation, without surface segregation of Se atoms and with an optically flat surface.
[1] J. P. Mailoa, A. J. Akey, C. B. Simmons, D. Hutchinson, J. Mathews, J. T. Sullivan, D. Recht, M. T. Winkler, J. S. Williams, J. M. Warrender, P. D. Persans, M. J. Aziz, and T. Buonassisi, Nat. Commun. 5, 3011 (2014).
[2] S. Zhou, F. Liu, S. Prucnal, K. Gao, M. Khalid, C. Baehtz, M. Posselt, W. Skorupa, and M. Helm, Sci. Rep. 5, 8329 (2015).
[3] I. Umezu, J. M. Warrender, S. Charnvanichborikarn, A. Kohno, J. S. Williams, M. Tabbal, D. G. Papazoglou, X. C.Zhang, and M. J. Aziz, J. Appl. Phys. 113, 213501 (2013).