The I–V characteristics of asymmetrically necked samples of high-resistivity silicon

The results of investigation of the I–V characteristics are presented for asymmetrically necked n -Si samples. It is established that the asymmetry of the I–V characteristic for the samples under investigation at the room and liquid-nitrogen temperatures in high electric fields is caused by the space-charge formation. At T = 78 K in the warm-electron region, the asymmetry of the I–V characteristic is caused by nonlocal relation between the electron mobility and the nonuniform electric-field intensity. It is found that the sample resistance at liquid-nitrogen temperature insignificantly increases after applying high electric-field pulses. The effect under observation is attributed to a decrease in the electron concentration in the necked section of the sample due to the redistribution of hot electrons between bulk and surface.