We investigated the effect of Indium (In) doping on the structural and electrical properties of Ti/Au/ TiO2:In/n-Si metal-oxide-semiconductor (MOS) devices. Sputtering grown TiO2 thin films on Si substrate were doped using two In-films with 15 nm and 50 nm thicknesses leading to two structures named Low Indium Doped (LID) sample and High Indium Doped (HID) sample, respectively. XRD analysis shows no diffraction pattern related to Indium indicating that In has been incorporated into the TiO2 lattice. Current-Voltage (I-V) characteristics show that rectification ratio at 2V is higher for HID sample than for LID sample. Evaluated barrier height, ϕ B0 , decreased while the ideality factor, n, increased with decreasing temperature. Such behavior is ascribed to barrier inhomogeneity that was assumed to have a Gaussian Distribution (GD) of barrier heights at interface. Evidence of such GD was confirmed by plotting ϕ B0 versus n. High value of mean barrier ϕ ̅ B0 and lower value of standard deviation (σ) of HID structure are due to indium doping which increases the barrier homogeneities. Finally, estimated Richardson constants A* are in good agreement with theoretic values (112 A/cm 2 K 2 ), particularly, for the HID structure.

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Current–voltage (I–V), capacitance–voltage–frequency (C–V–f) and conductance–voltage–frequency (G/[Formula: see text]–V–f) characteristics of Molecular Beam Epitaxy (MBE)-deposited Fe/n-Si[Formula: see text]Ge[Formula: see text] (FM1) and Pt/[Formula: see text]-Si[Formula: see text]Ge[Formula: see text](PM2) (111) orientated Schottky barrier diodes (SBDs) have been investigated at room-temperature. Barrier height ([Formula: see text]), ideality factor (n) and series resistance (R[Formula: see text]) were extracted. Dominant current conduction mechanisms were determined. They revealed that Poole–Frenkel-type conduction mechanism dominated reverse current. Differences in shunt resistance confirmed the difference found in leakage current. Under forward bias, quasi-ohmic conduction is found at low voltage regions and space charge-limited conduction (SCLC) at higher voltage regions for both SBDs. Density of interface states (N[Formula: see text]) indicated a difference in interface reactivity. Distribution profiles of series resistance (R[Formula: see text]) with bias gives a peak in depletion region at low-frequencies that disappears with increasing frequencies. These results show that interface states density and series resistance of Schottky diodes are important parameters that strongly influence electrical properties of FM1 and PM2 structures.

Dielectric properties of As grown and irradiated Ti /Au/GaAsN Schottky diodes with 1.2%N are investigated using capacitance/conductance-voltage measurements in 90 -290 K temperature range and 50-2000 kHz frequency range. Extracted parameters are interface state density, series resistance, dielectric constant, dielectric loss, tangent loss and ac conductivity. It is shown that exposure to γ-rays irradiation leads to reduction in effective trap density believed to result from radiation-induced traps annulations. An increase in series resistance is attributed to a net doping reduction. Dielectric constant (ε') shows usual step-like transitions with corresponding relaxation peaks in dielectric loss. These peaks shift towards lower temperature as frequency decrease. Temperature dependent ac conductivity followed an Arrhenius relation with activation energy of 153 meV in the 200-290 K temperature range witch correspond to As vacancy. The results indicate that γ-rays irradiation improves the dielectric and electrical properties of the diode due to the defect annealing effect.