Substrate temperature effects on the structural, compositional, and electrical properties of VO 2 thin films deposited by pulsed laser deposition

The vanadium dioxide (VO 2 ) thin films were deposited on silicon (100) substrate using the pulsed laser deposition technique. The thin films were deposited at different substrate temperatures (500°C, 600°C, 700°C, and 800°C) while keeping all the other parameters constant. X‐ray diffraction confirmed the crystalline VO 2 (B) and VO 2 (M) phase formation at different substrate temperatures. X‐ray photoelectron spectroscopy analysis showed the presence of V 4+ and V 5+ charge states in all the deposited thin films which confirms that the deposited films mainly consist of VO 2 and V 2 O 5 . An increase in the VO 2 /V 2 O 5 ratio has been observed in the films deposited at higher substrate temperatures (700°C and 800°C). Scanning electron microscope micrographs revealed different surface morphologies of the thin films deposited at different substrate temperatures. The electrical properties showed the sharp semiconductor to metal transition behavior with approximately 2 orders of magnitude for the VO 2 thin film deposited at 800°C. The transition temperature for heating and cooling cycles as low as 46.2°C and 42°C, respectively, has been observed which is related to the smaller difference in the interplanar spacing between the as‐deposited thin film and the standard rutile VO 2 as well as to the lattice strain of approximately −1.2%.