  Chalcogen-hyperdoped silicon shows potential applications in silicon-based
infrared photodetectors and intermediate band solar cells. Due to the low solid
solubility limits of chalcogen elements in silicon, these materials were
previously realized by femtosecond or nanosecond laser annealing of implanted
silicon or bare silicon in certain background gases. The high energy density
deposited on the silicon surface leads to a liquid phase and the fast
recrystallization velocity allows trapping of chalcogen into the silicon
matrix. However, this method encounters the problem of surface segregation. In
this paper, we propose a solid phase processing by flash-lamp annealing in the
millisecond range, which is in between the conventional rapid thermal annealing
and pulsed laser annealing. Flash lamp annealed selenium-implanted silicon
shows a substitutional fraction of around 70% with an implanted concentration
up to 2.3%. The resistivity is lower and the carrier mobility is higher than
those of nanosecond pulsed laser annealed samples. Our results show that
flash-lamp annealing is superior to laser annealing in preventing surface
segregation and in allowing scalability.
