A Test for the Applicability of the Field Emission Law to Studying Multitip Field Emitters by Analysis of the Power Index of the Preexponential Voltage Factor

Resumo

A test for the correspondence of experimental current–voltage (I–U) characteristics to the regime of cold field emission is described. The proposed method is based on the variation of voltage power index in semilogarithmic coordinates ln(I/U ^k)–1/U and the statistical analysis of fluctuations in experimental data. It is established that I–U characteristics obtained by the method of fast high-voltage sweep provide a better correspondence to the field emission law than do the characteristics measured using slow voltage sweep. The test sample was a multitip nanocomposite field emitter based on carbon nanotubes in a polymer matrix. Experimental data have been processed in modified Fowler–Nordheim coordinates with power exponent k = 1.24.