Excess carriers lifetime in InP single crystals: Radiative versus nonradiative recombination

We present a comprehensive and systematic study of the minority and majorit y carrier lifetimes in InP single crystals doped in the range of 1x10(15)-4 x10(18) cm(-3). Radiative recombination dominates in undoped InP, because t he Shockley-Read-Hall lifetime is very long (> 10 mu s). For S or Sn doped n-type InP with intermediate doping concentration, nonradiative recombinati on is dominant under low injection conditions, hence the effective lifetime increases with increasing the injection level. On the other hand, the effe ctive lifetime decreases with increasing the injection level under high exc itation conditions due to radiative recombination. Thus, the effective life time has the largest value (140 ns for S-doped InP with majority carrier co ncentration n(0)=2x10(17) cm(-3), and 110 ns for Sn-doped InP with n(0)=3x1 0(17) cm(-3)) for an injection level of around 1x10(17) cm(-3). Such inform ation is important for the design of devices that operate under high inject ion levels like lasers and concentrated solar cells. In p-InP, nonradiative recombination and trapping dominate even in low doped samples and the effe ctive lifetimes are much shorter than in n-InP. (C) 1999 American Institute of Physics. [S0021-8979(99)05912-5].