| The thickness dependence of the thermal emf and thermoelectric power of thin film Cu/Constantan thermocouples showed nearly bulklike behavior when the thickness of each element film comprising the thermocouples was greater than∼3300Å. The changes in electron transport properties(resisitivity, Hall coefficient, carrier concentration, and mobility) of the $quot;as-deposited$quot; and the $quot;vacuum-annnealed$quot; Cu element films showed three different regions of thickness dependence ; region - I (t≥1500Å), - II (1500≥t≥3300Å), and - III (t≥3300Å). Each region was attributed to the differences in the size-, grain boundary-effect and the effect of the saturated structural defects. In Constantan film, only two such regions(t≥1000Å and t≥1000Å) were observed, and the main reason of it was believed to be the alloying effect of evaporants(Cu and Ni) as well as the rapid deposition rate. The increased or decreased thermoelectric power of thin film thermocouples with the thickness or the annealing treatment was directly related to the facts that the electron transport properties of both element films were subjected to change by the above mentioned effects. |
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