DEGRADED NOISE CHARACTERISTICS OF SUBMICROMETER AREA FIELD-EFFECT TRANSISTORS SUBJECTED TO PLASMA-ETCHING AND FOWLER-NORDHEIM STRESS

The effects of reactive ion etching (RIE) and Fowler-Nordheim (FN) gate current stresses upon both the 1/f(gamma) and random telegraph signal (RTS) noise characteristics of submicrometer gate area metal oxide semiconductor field-effect transistors has been analyzed. While control devices exhibit the Lorentzian noise spectra and discrete switching behavior attributable to single oxide defects, the first layer metal antenna devices exhibit degraded RTSs and near ideal 1/f noise characteristics. An evolution of this 1/f behavior has been reproduced in control devices by subjecting them to a series of UV illuminated FN gate current stresses. Results of this study suggest that multiple oxide traps with a distribution in time constants are generated during RIE and that the amount of oxide degradation generated during plasma etching may be more substantial than that produced during plasma ashing. (C) 1995 American Institute of Physics.