OPTICAL EFFECTS OF DOPED TOP LAYERS IN SILICON-ON-INSULATOR STRUCTURES FORMED BY ION-IMPLANTATION

Arsenic ions were implanted into silicon-on-insulator (SOI) structures at an incident energy of 100 keV to a dose of 2 x 10(15) cm(-2). Cond uctive top layers were formed in the SOI structures after annealing at 1200 degrees C for 20 s. Infrared reflection spectra in the wave numb er range of 1500-5000 cm(-1) were measured and interference fringes, r elated to free-carrier plasma effects, were observed. By detailed theo retical analysis and computer simulation of infrared reflection spectr a, the carrier concentration, the carrier mobility, and the carrier ac tivation efficiency were obtained. The physical interpretation of the results and a critical discussion of the sensitivity of the data, fitt ed to variation in the parameters, are given.