Electrical Conductivity of Silicon Dioxide Thermally Grown on Silicon

摘要

DC and ac electrical conductivities of silicon dioxide thermally grown on p-(boron-doped) and n-type(phosphorous-doped) silicon have been measured in the temperature range of 25 -1100 C. Total dc conductivities varied form 10 to the -9th to 10 to the -16th per ohns/cm in the temperature range of 25-960 C. Arrhenius plots for total dc conductivities of SiO2 grown on both the substrates exhibit two regions. Below 450 C, the conductivities were independent of temperature and are suggested to be governed by impurities. Above 450 C, the total dc conductivities increased with increase in temperature. The activation energies of conduction in the temperature range 500 - 960 C were estimated to be 1.65 and 2.10 eV for SiO2 grown on p- and n-type silicon, respectively. DC polarization measurements carried out in this temperature range suggest that conduction in SiO2 is ionic as well as electronic. The ionic conduction is believed predominantly to be due to the transport of oxygen ions. AC conductivities were also measured in the temperature range of 550 -1100 C. The activation energies for the conduction in this temperature range were estimated to be 1.55 eV for SiO2 on p-type silicon and 1.86 eV for SiO2 on n-type silicon. these values are in close agreement with the values reported in the literature. AC conductivity of SiO2 grown on n-type silicon. These values are in close agreement with the values reported in the literature. AC conductivity of Si02 grown on n-type silicon was found to be lower that that of SiO2 grown on p-type silicon. (Author)