MODELIZATION AND CHARACTERIZATION OF AU INSB/INP SCHOTTKY SYSTEMS AS A FUNCTION OF TEMPERATURE/

This work attempts to characterize the Au/InP Schottky diode at differ ent temperatures (in the range 300-425 K). The InP surface is restruct ured with an InSb thin film with several monolayers. I(V) analysis ver sus different temperatures gives the saturation current variation I-s( 2 x 10(-5)-7 x 10(-5) A), the mean ideality factor (1.7-1.24), the bar rier height (0.47-0.45 V), and finally the serial resistance R-s varia tions (85-19 Omega). The doping concentration N-d and the diffusion vo ltage V are calculated using the C(V) characteristics. The concentrati on N-d is 3 x 10(15) cm(-3) at room temperature and increases with the rmal activation to 7 x 10(15) cm(-3) at 425 K. Nevertheless, the diffu sion voltage V-d is reversibly proportional to the doping concentratio n N-d and decreases from 33.7 x 10(-2) to 29 x 10(-2) V. The mean inte rfacial state density N-ss decreases with increasing temperature, from 4.33 x 10(12) to 10(12) cm(-2).eV(-1). This improvement is the result of molecular restructuring and reordering at the Au/InP interface. Fo r temperatures less than 375 K, the C(V) characteristic is controlled by an important interfacial state density and/or the presence of deep donor levels in the semiconductor bulk. At temperatures greater than 3 75 K, the C-2(V) curve is linear and the deep donor levels disappear; The traps effect is also reduced. (C) 1998 Elsevier Science S.A. All r ights reserved.