Evaluation of temperature dependent electrical transport parameters in Fe3O4/SiO2/n-Si metal–insulator-semiconductor (MIS) type Schottky barrier heterojunction in a wide temperature range

Abstract

In this manuscript, we reported the electrical characteristics and structural analysis of In/Fe3O4/SiO2/n-Si/In MIS-type SBD heterostructure comprehensively in the temperature range 10–300 K using I–V, XRD, TEM and AFM measurements. Pulsed laser deposition in association with DC magnetron sputtering techniques has been utilized to fabricate the proposed In/Fe3O4/SiO2/n-Si/In heterojunction. The fabricated heterojunction revealed that the I–V curves are non-linear and asymmetric in nature. Using these I–V curves in the forward-bias region, SBH is calculated as 0.02 eV at 10 K and 0.74 eV at 300 K. On the other hand, the ideality factor (n) value was calculated as 7.55 at 10 K and 1.37 at 300 K. The series resistance (RS) values were also evaluated using Chenug’s method and the values were 1121 Ω at 10 K and 334 Ω at 300 K. The dependence of important diode parameters such as SBH, ‘n’ and ‘RS’ on measurement temperature was effectively explained firstly on account of triple Gaussian distribution of barrier heights with the help of barrier inhomogeneities of the prepared heterojunction. The value of the Richardson’s constant calculated for the fabricated In/Fe3O4/SiO2/n-Si/In heterojunction in the 110–300 K temperature regime was calculated to be 115.26 A/cm2K2 and is approximately equal to the theoretical value of 120 A/cm2K2 for n-type Si. In addition, the higher value (greater than one) of ideality factor at all operating temperatures from 10–300 K demonstrated that the probable current transport across the Fe3O4/SiO2/n-Si junction is not only due to the thermionic emission (TE) mechanism. Hence, to reveal the origin of current transport mechanism i.e., other than TE, we noticed that the governing current transport process through the fabricated hetrojunction is mainly due to the tunneling assisted Poole–Frenkel class of emission across the Fe3O4/SiO2/n-Si junction which is found to be temperature-dependent.