ORIGINAL PAPER Analysis of Double Gaussian Distribution at the Interface of Ni/Ta 2 O 5 /P-Si Schottky Barrier Diodes Using Temperature Dependent Current-Voltage (I-V) Measurements Nallabala Nanda Kumar Reddy 1 & Chandramohan Kukkambakam 2 & V. Manjunath 3 & Vasudeva Reddy Minnam Reddy 4 Received: 20 November 2019 /Accepted: 30 January 2020 # Springer Nature B.V. 2020 Abstract The electrical properties have been investigated for Ni/Ta 2 O 5 /p-Si Metal/insulator/semiconductor SBD in the temperature regime 175–400 K. The electrical parameters were analyzed using current-voltage characteristics as a function of operating temperature. It is observed that the Schottky barrier height increased whereas ideality factor and series resistance decreased with increasing the operating temperature. The characteristic temperature (T o ) value calculated from Norde and Cheung methods was compared. This analysis showed that T o value extracted from both the techniques are in close agreement with each other. Experimental results revealed that the thermal coefficient was -4.5 mV/K. The Gaussian distribution of the barrier height was estimated from the plot of zero-bias barrier height (Φ bo ) versus 1/2kT plot and the estimated value of (Φ bo ) of 0.92 eV and 0.79 eV with standard deviation (σ 0 ) of 0.023 V and 0.014 V, respectively. The mean BH and the Richardson constant values were determined using ln (I o /T 2 )-q 2 σ 2 0 /2(kT) 2 versus 1000/T plot and were 0.89 eVand 0.76 eVand 30.03 and 26.85 A/cm -2 K -2 , respectively. In addition to the thermionic emission process, two more conduction mechanisms such as Poole-Frenkel emission in the temperature regime 175–275 K and Schottky emission dominant beyond 300 K temperature were noticed. Keywords MIS Schottky barrier diode . Series resistance . Ta2O5 dielectric layer . Double Gausssian Disribution 1 Introduction Presently, the development of semiconductor devices in nano- scale regime creates a huge demand for the study of high-k dielectric materials as they became the prime constituents in almost all Si-based devices [1, 2]. The reduction of SiO 2 high- k insulating layer thickness less than few nanometers is sus- ceptible to direct tunneling of electrons causing a severe leakage current issue in devices fabricated on Si semiconduc- tor [3]. Thus, various high-k materials such as HfO 2 , ZrO 2 , Y 2 O 3 , La 2 O 3 , CeO 2 and Ta 2 O 5 are presently under consider- ation to replace the conventional SiO 2 layer due to the above said limiting factors. Among these high-k dielectrics, tantalum pentoxide (Ta 2 O 5 ) appear to be the most capable material owing to its higher dielectric constant, tolerable breakdown voltage, reasonably low leakage currents and thermal/ chemical stability at higher temperatures [4, 5]. Due to these outstanding characteristic properties, Ta 2 O 5 found applica- tions such as coatings [6], high storage capacitors [7], electrochromic devices [8] and catalysts [9]. Previously, vari- ous research groups have utilized RF sputtering [9], sol-gel [10] and pulsed laser deposition [11] to deposit the Ta 2 O 5 films onto various substrates. The deposition of metal film onto silicon semiconductor surface is acknowledged as metal-semiconductor (MS) contacts/Schottky barrier diodes (SBDs) which is very simple and plays a significant key role in all most all semiconductor based electronic devices such as integrated circuits, optoelec- tronics and devices functioning in the microwave region [12]. The performance of these devices for instance device * Nallabala Nanda Kumar Reddy nandasvu@gmail.com * Vasudeva Reddy Minnam Reddy drmvasudr9@gmail.com 1 Department of Physics, Madanapalle Institute of Technology and Science, Madanapalle, A.P 517325, India 2 Department of Chemistry, Madanapalle Institute of Technology and Science, Madanapalle, A.P 517325, India 3 Department of Physics, Sri Padmavati Mahila Visvavidyalayam, Tirupati, A.P 517 501, India 4 School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea Silicon https://doi.org/10.1007/s12633-020-00407-3