Fabrication of Sub-Micron Tungsten Carbide (WCx)/Amorphous Carbon (a-C) Stacked Junction By Beam-Induced Reaction Processes

Deposition of a carbon microfilm was performed by an electron-beam-induced deposition technique using scanning electron microscopy, and its electrical as well as optical properties were characterized. Peaks originated from a diamond-like carbon (DLC) were observed by Raman scattering spectroscopy and it was indicated that the deposited film consisted of amorphous carbon (a-C). Its electrical characteristics were studied using metal-insulator-metal diodes. The I-V curve of the diode showed nonlinear characteristics, and a dielectric constant was estimated at about 5. Furthermore, a tungsten carbide (WCx) film was grown by an ion-beam-induced deposition technique, and it was used in a WCx/a-C/WCx stacked junction of submicron size. It could be estimated from the dependence of the thermionic emission current on temperatures that an intrinsic barrier height in this WCx/a-C system was approximately 0.19 eV.