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Co-doping of Mg into chemically stable TiO 2 thin film is attractive for deep UV detection. In this report, we have fabricated ∼110 nm undoped TiO 2 thin film and Mg doped TiO 2 thin film based photodetectors on p-type Silicone substrates. The Mg doped TiO 2 thin film shows good hydrophobicity. The undoped TiO 2 thin film shows low deep UV besides high responsivity in the visible region. The Mg:TiO 2 photodetector shows a maximum of four times superior light sensitivity as compared to undoped TiO 2 thin film at 200 nm illumination. The Mg:TiO 2 thin film shows the countable temporal response at 290 nm but the detector possesses low responsivity in the visible region. • Synthesis of Mg:TiO 2 TF using E-beam evaporation system. • The main bandgap of TiO 2 was enhanced to 4.15 eV after incorporation of Mg. • Mg:TiO 2 TF shows good hydrophobicity as compared to undoped TiO 2 TF. • The Mg:TiO 2 UVPD shows a maximum of four times sensitivity at 200 nm. • The Mg:TiO 2 TF device shows superior temporal response at 290 nm. [ABSTRACT FROM AUTHOR]

We have fabricated VO 2 nano-columns (NCs) on the aluminized quartz glass substrates using glancing angle deposition (GLAD) technique inside the electron beam (e-beam) evaporator chamber. An e-beam deposited TiO 2 thin cap-layer has been introduced on the top of the VO 2 NCs to protect VO 2 phase which is usually unstable and turns to stable higher oxidation state, i.e., V 2 O 5. The X-ray diffraction (XRD) analysis of TiO 2 thin film (TF) coated VO 2 NCs shows the presence of VO 2 phases along with the other oxidation states. The Fourier-Transform-Infrared-Spectroscopy (FTIR) confirms the presence of Ti–O–V, V–O vibrations bands in VO 2 NCs/TiO 2 TF samples. The VO 2 NCs/TiO 2 TF sample possesses a sharp drop (~103 order) in resistance at the transition temperature (T c) ~66 °C. This sample also shows a stable semiconducting to metallic phase (vice versa as well) transition temperature (PTT) hysteresis even after one month which ensures the stable performance in terms of phase transition characteristic. Small-radius polaron model (SRPM) is used to calculate the sheet resistance of the VO 2 NCs, where we consider the effect of thermal lattice vibrations on the overlap integral of the crystal atoms. The temperature dependency of constants A and ε have been observed uniquely. The Fermi-Dirac (F-D), Migdal distribution (MD) model have been taken into account for the first time to calculate the conduction band carrier density of VO 2 NCs and ratio of the resistance in the semiconducting (R S), metallic phase (R M) is also calculated. The calculated electron concentration (n c) is 3.1 × 1019 cm-3 at the point of PTT (66 °C). [ABSTRACT FROM AUTHOR]