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Article Citation - WoS: 12Citation - Scopus: 14Analysis of Double Gaussian Distribution on Barrier Inhomogeneity in a Au/n-4H SiC Schottky Diode(Springer, 2021) Gullu, H. H.; Sirin, D. Seme; Yildiz, D. E.A n-4H SiC based diode is fabricated by an Au front metal contact to provide rectification at the metal-semiconductor (MS) junction, and a back ohmic contact is also obtained using Au metal with post-thermal heating. MS diode characteristics are investigated by current-voltage (I - V) measurements with a wide range of temperature from 80 K to 300 K. At each temperature, rectifying behavior is achieved and it is improved with an increase in temperature. Barrier height and ideality factor are calculated according to the thermionic emission (TE) model from linearity in the forward bias region of the ln(I) versus V plot. The experimental zero-bias barrier height (Phi(b0)) values are in a good agreement with literature, and at around room temperature the ideality factor (n) reaches unity. At saturation regions in I - V curves, parasitic resistance values are derived by Ohm's law and the series resistance values are also reevaluated by Cheung's relation. Detailed I - V analysis is performed by modifying the TE model with an approximation of low barrier patches embedded in the main barrier height. Two linear relations in the characteristic plots of Phi(b0) and n indicate that double Gaussian distribution is a suitable current conduction model via localized barrier patches at low temperatures. Additionally, reverse bias current flow is analyzed under the dominant effect of Poole-Frenkel emission associated with the interfacial traps. According to the characteristic electric field-dependent current density plot, emission barrier height and relative dielectric constant for n-4H SiC are calculated.Article Citation - WoS: 7Citation - Scopus: 8Effect of Tio2 Thin Film With Different Dopants in Bringing Au-Metal Into a Contact With N-Si(Springer, 2022) Yildiz, D. E.; Gullu, H. H.; Cavus, H. KanburIn this work, effects of TiO2 contribution together with two different doping as graphene oxide (GO) and rubidium fluoride (RbF) are investigated at the interface of Au/n-Si metal-semiconductor (MS) diode. Diode characteristics are mainly evaluated from current-voltage measurements and values of barrier height and ideality factor are compared to the diodes with and without doping in interface layer. Although existence of interface layer increases these values, there is a decrease with adapting GO and RbF to the TiO2 structure. In addition, series and shunt resistance values are calculated with interface layer, and resistance effect is also discussed by Norde's and Cheung's functions. Forward biased carrier transport mechanism is evaluated under the presence of interface states by thermionic emission model and density of interface trap states is also discussed. At the reverse biased region, field effected thermionic emission model is found to be dominant flow mechanism, and leakage current behavior is explained by Schottky effect. Solar simulator with different illumination intensities is used to investigate photo-generated carrier contribution and photo-response of the diodes.
