Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

Doping allows us to modify semiconductor materials for desired electrical, optical and magnetic properties. The solubility limit is a fundamental barrier for dopants incorporated into a specific semiconductor. Hyperdoping refers to doping a semiconductor much beyond the corresponding solid solubility limit and often results in exotic properties. For example, Ga hyperdoped Ge reveals superconductivity and Mn hyperdoped GaAs represents a typical ferromagnetic semiconductor. Ion implantation followed by annealing is a well-established method to dope Si and Ge. This approach has been maturely integrated with the IC industry production line. However, being applied to hyperdoping, the annealing duration has to be shortened to millisecond or even nanosecond. The intrinsic physical parameters related to dopants and semiconductors (e.g. Solubility, diffusivity, melting point and thermal conductivity) have to be considered to choose the right annealing time regime. In this talk, we propose that ion implantation combined with flash lamp annealing in millisecond and pulsed laser melting in nanosecond can be a versatile approach to fabricate hyperdoped semiconductors. The examples include magnetic semiconductors [1-4], highly mismatched semiconductor alloys (Ge1-xSnx [5] and GaAs1-xNx [6]), n++ Ge [7] and chalcogen doped Si [8, 9].

[1] M. Khalid, et al., Phys. Rev. B, 89, 121301(R) (2014).
[2] S. Zhou, J. Phys. D: Appl. Phys,. 48, 263001 (2015).
[3] S. Prucnal, et al., Phys. Rev. B, 92, 222407 (2015).
[4] Y. Yuan, et al., ACS Appl. Mater. Interfaces, 8, 3912 (2016).
[5] K. Gao, et al., Appl. Phys. Lett., 105, 042107 (2014).
[6] K. Gao, et al., Appl. Phys. Lett.., 105, 012107 (2014) .
[7] S. Prucnal, et al., Sci. Reports, 6, 27643 (2016).
[8] S. Zhou, et al., Sci. Reports, 5, 8329 (2015).
[9] Y. Berencén, et al., ACS Photonics, submitted (2016).