Research Information System
Thesis Type: Doctorate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2015
Student: ELİF MARIL
Supervisor: ŞEMSETTİN ALTINDAL
Abstract:Current transport mechanisms (CTMs) of Au/Ca3Co4Ga0,001Ox/n-Si/Au structures were investigated in the temperature range of 80-340K. LnI-V plots show two distinct linear regions corresponding to low (0,075-0,250 V) and moderate (0,27-0,70 V) biases. The barrier height (BH) Bo and ideality factor (n) values were obtained from the intercept and slope of these plots. While Bo increases with increasing temperature, n decreases. Bo and (n-1-1) vs q/2kT and Bo vs n plots were drawn to get an evidence of Gaussian distribution (GD) of the BHs. These plots, show also two linear regions corresponding to low (80-160K) and high (200-340K) temperatures which are called as LTR and HTR. Mean value ( ̅Bo) and standard deviation (s) were extracted from the intercept and slope of ΦBo vs q/2kT plots for two linear regions as 0,382 eV, 0,060 V for LTR and 0,850 eV, 0,135 V for HTR at low biases and 0,364 eV, 0,059 V for LTR and 0,806 eV, 0,132 V for HTR at moderate biases. ̅Bo and Richardson constant (A*) values were also obtained from the intercept and slope of the modified Richardson (Ln(Io/T2)-(q2s2/2k2T2) vs q/kT) plots as 131,81 Acm-2K-2, 0,381 eV for LTR and 129,35 Acm-2K-2, 0,854 eV for HTR at low biases and 148,01 Acm-2K-2, 0,377 eV for LTR and 143,77 A.cm-2K-2, 0,812 eV for HTR at high biases. CTM can be successfully explain in terms of thermionic emission (TE) with the double GD of BHs. Reverse bias Ln (Ir/Er) vs E0,5 plots show also straight lines with different slopes. Both the intercepts B(T) and slopes m(T) values versus q/kT plots were drawn. These results show that the IR-VR characteristics can be well described by the electric field dependence so the dominant conduction mechanisms are either Frenkel-Poole (FP) emission or Schottky emision (SE). The i and t values were found as 3,1 and 37,1 meV. t is considerably low and the value of i (3,1) is closed to conventional of SiO2 layer (3,8). These results confirmed that (Ca3Co4Ga0,001Ox) layer can be used instead of a conventional of SiO2 layer in the terms of flexibility, easy production and low cost.