Thermal Annealing of Pb Films on Modified Silicon Surface: Electrical Conductance Measurement

The electron transport properties of thin Pb films on Si(111)-(6x6) Au surface are studied experimentally using the four-point probe method and reflection high-energy electron diffraction system in UHV condition. We have measured the electrical conductance of the substrate with deposited at liquid nitrogen temperature Pb atoms during annealing and cooling down. We have found that the conductance increases during this process and from comparison of both heating and cooling curves the Pb recrystallization temperature was determined. Moreover, it was shown that 4 ML thick Pb film reveals temperature dependence of the conductance corresponding to the metallic bulk structure with the temperature coefficient of resistivity equal to 0.0036 1/K. To describe theoretically the conductance of thin Pb films the modified Trivedi-Ashcroft theory with temperature dependence of the roughness function was used in our calculations.