부산대학교 도서관

We report on the nucleation, growth, percolation, and crystalline transition of ultrathin layers of molybdenum deposited on float glass substrate by in situ electrical properties. The transition from insulating to metallic state (I-M) is shown as a function of molybdenum film thickness and sheet resistance. In the island growth regime, the electrical conductance (G) has two exponential dependencies on thickness (t), namely, log G-B1∝t and log G-B2∝t, explained as the anisotropic and isotropic growth of islands, respectively. In the I-M transition region, the electrical conductance of the films follows the scaling law G∝(t-tc)q. The value of critical exponent q determined from the present experiments agrees well with the theoretically predicted values for the critical exponent of conductivity in a two-dimensional percolating system. The amorphous to crystalline transition is also observed. The microscopic picture of film growth, derived from in situ sheet resistance measurements shows good agreement with that predicted by the percolation theory. [ABSTRACT FROM AUTHOR]