Low-field microplasma breakdown in a-As_2Se_3 thin films

摘要

It is shown that increasing external field stimulates appearance of the conductive microplasma channels in a-As_2Se_3 thin films. Cooling a sample under high field causes the disabling of microplasmas and decreases the sample conductance by several orders of magnitude in a rather narrow temperature range. The diameter of a microplasma channel was estimated to be one nanometer. We conclude that some negative centers near the metal-a-As_2Se_3 interface are causing a local barrier height lowering, stimulating the injection of carriers and formation of a microplasma.