Tunable plasmonics in heavily doped GaAs via ion implantation and sub-second annealing

Semiconductors with ultra-high doping level are attractive for the near- and mid-infrared plasmonics. The III-V compound semiconductors are characterized by high electron mobility and low effective mass, where the plasma edge can be tuned by tailoring the doping level. In this work, we present the formation of heavily doped p- and n-type GaAs utilizing ion implantation of Te, S and Zn, followed by sub-second annealing. We demonstrate that either the millisecond range flash lamp annealing (solid phase epitaxy) or nanosecond range pulsed laser annealing (liquid phase epitaxy) is able to recrystallized the implanted layers and electrically activate the dopants.The carrier concentration in the heavily doped p- and n-type GaAs with sub-second annealing treatment is in the range of 1019~1020 cm-3. The plasmonic properties of implanted and annealed GaAs samples were investigated by Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The obtained ultra-highly GaAs films display a room-temperature plasma frequency above 2200 cm-1, which enables to exploit the plasmonic properties of GaAs for sensing in the mid-infrared spectral range.