Avalanche breakdown in n-hexane

Abstract

Time lags to breakdown in n-hexane have been measured in high over-voltages, using approximately 100 ns width rectangular pulses. At a constant field, the time lags are divided into two types, N and B, at a 'critical distance' d. Above d_c, Laue plots have almost similar kinked-line characteristics; below d_c, a straight line is obtained. From the prebreakdown current estimated from the voltage waveforms, the ionisation coefficient, which increases with increasing applied fields, is estimated to be 6.4*10³ cm^-1 at 3.5 MV cm^-1, provided a single-electron avalanche is occurring.