Design and fabrication of thermopower and electrical resistivity setup for bulk and thin film systems

Abstract

An experimental setup has been designed and fabricated with a new configuration for measuring both thermopower as well as resistivity of different type of samples (bulk and thin film) in the temperature range 80–300 K. The setup utilizes a differential method for measuring the thermopower of samples. The sample holder in the present setup has been designed in such a way that, samples of lengths ∼2.5–15 mm can be loaded easily with the help of spring–shaft arrangement. Electrical leads, as well as controlled ΔT by chromel-AuFe (0.07 %) thermocouple, are mounted on the copper blocks. Manganin wires of resistance 50 Ω are used as heating elements and wound on the copper blocks. Generated emf of the sample and the thermocouple are measured using nanovoltmeter. The present configuration allows simple way of applying temperature difference to bulk and thin film systems. The setup allows continuous ΔT control across the sample by chromel-AuFe (0.07 %) thermocouple to achieve accuracy and precision with the nanovoltmeter, scanner switching system and Visual Basics software programme used for automatic measurements. The measurements are carried on standard bulk samples Mn, Mo and Mo thin film. Results are well in agreement with reported values.