Title :
AC characteristics of Cr/p+a-Si:H/V analog switching devices
Author :
Hu, J. ; Hajto, Janos ; Snell, Anthony J. ; Rose, M.J.
Author_Institution :
Sch. of Eng., Napier Univ., Edinburgh, UK
fDate :
9/1/2000 12:00:00 AM
Abstract :
Experimental results on the ac characteristics of electro-formed Cr/p+ hydrogenated amorphous silicon (a-Si:H)/V thin film memory devices are presented. The impedance spectrum of the memory switching device has been measured over a wide frequency range from 1 Hz-32 MHz while keeping the ac voltage amplitude below 0.02 V. Simulation of the measured impedance spectrum using an equivalent circuit indicates that the capacitance associated with a conducting filament tends to increase as the memory resistance decreases. This is explained on the basis of an activated tunnelling mechanism. Charge transport is dominated by electron tunnelling via metallic particles in the filament, and hence small changes in interparticle spacing influences the tunnelling process considerately, leading to changes in both memory resistance and effective dielectric constant
Keywords :
amorphous semiconductors; analogue storage; cobalt; elemental semiconductors; equivalent circuits; hydrogen; metal-semiconductor-metal structures; permittivity; semiconductor storage; semiconductor switches; silicon; tunnelling; vanadium; 1 Hz to 32 MHz; AC characteristics; Cr-Si:H-V; Cr/p+a-Si:H/V thin film analog memory switching device; charge transport; effective dielectric constant; electroforming; electron tunnelling; equivalent circuit; impedance spectrum; Amorphous silicon; Capacitance measurement; Chromium; Electrical resistance measurement; Frequency measurement; Impedance measurement; Semiconductor thin films; Thin film circuits; Thin film devices; Tunneling;
Journal_Title :
Electron Devices, IEEE Transactions on