Electrical properties of low pressure chemical vapor deposited silicon nitride thin films for temperatures up to 650 °C

The results of a study on electrical conduction in low pressure chemical vapor deposited silicon nitride thin films for temperatures up to 650 °C are described. Current density versus electrical field characteristics are measured as a function of temperature for 100 and 200 nm thick stoichiometric (Si3N4) and low stress silicon-rich (SiRN) films. For high E-fields and temperatures up to 500 °C conduction through Si3N4 can be described well by Frenkel–Poole transport with a barrier height of ∼1.10 eV, whereas for SiRN films Frenkel–Poole conduction prevails up to 350 °C with a barrier height of ∼0.92 eV. For higher temperatures, dielectric breakdown of the Si3N4 and SiRN films occurred before the E-field was reached above which Frenkel–Poole conduction dominates. A design graph is given that describes the maximum E-field that can be applied over silicon nitride films at high temperatures before electrical breakdown occurs.