GOOD QUALITY AL SINX-H/INP METAL-INSULATOR-SEMICONDUCTOR DEVICES OBTAINED WITH ELECTRON-CYCLOTRON-RESONANCE PLASMA METHOD/

We have obtained Al/SiNx:H/InP metal-insulator-semiconductor devices d epositing SiNx:H thin films by the electron cyclotron resonance plasma method at 200 degrees C. The electrical properties of the structures were analyzed according to capacitance-voltage and deep level transien t spectroscopy measurements. We deduce an inverse correlation between the insulator composition-the N/Si ratio-and the density of interface traps: those films with the maximum N/Si ratio (1.49) produce devices with the minimum trap density-2 x 10(12) cm(-2) eV(-1) at 0.42 eV. abo ve the midgap. We explain the influence of film composition on the int erface trap density in terms of a substitution of phosphorous vacancie s at the InP surface, V-p, by N atoms coming from the insulator, N-Vp. The values obtained in our research for the interface trap distributi on were similar to other published results for devices that use chemic al and/or physical passivation processes of the InP surface prior to t he deposition of the insulator. (C) 1998 American Institute of Physics .