Electrical Characterization of Low Nitrogen Content Plasma Deposited and Rapid Thermal Annealed Al/SiNx:H/InP Metal-Insulator-Semiconductor Structures

Abstract

The influence of the dielectric composition and post deposition rapid thermal annealing (RTA) treatments on the electrical characteristics of low nitrogen content plasma-deposited Al/SiNx:H/InP structures were analyzed. To obtain the interface state density, deep level transient spectroscopy (DLTS) measurements were carried out. We have also evaluated the insulator damage density, the so-called disorder-induced gap states (DIGS), by means of conductance transient analysis. As for the dielectric composition, both the x=0.97 and x=1.43 values provide interfacial state density and DIGS damage values of the same order of magnitude. In the x=0.97 case, RTA treatments reduce the insulator damage moving it towards the interface. In the x=1.43 case this behavior is only observed for RTA temperatures lower than 500°C. So, moderate temperature (<500°C) RTA treatments improve DIGS damage. This is an important result in terms of fabricating bi-layered metal-insulator-semiconductor (MIS) structures that not only have good-quality interfaces, but also good dielectric properties.