Contents lists available at ScienceDirect Optik journal homepage: www.elsevier.com/locate/ijleo Original research article Elicitation of barrier height of rapid thermal annealed Bi-nSi Schottky photodetector using various methods: A comparative study Raid A. Ismail a, ⁎ , Khaleel I. Hassoon a , Omar A. Abdulrazzaq b a School of Applied Sciences, University of Technology, Baghdad, Iraq b Renewable Energy and Environment Research Center, Corporation of Research and Industrial Development, Baghdad, Iraq ARTICLE INFO Keywords: Bi-Si contact Barrier height RTA Band diagram ABSTRACT The feasibility of making Schottky barriers from Bi-nSi diode has been demonstrated. The barrier height (Ø Bn ) of the Schottky contact was estimated via four creditable methods: I-V in the dark, I- V under illumination, C-V, and Fowler plot method. Such a study has been done for the frst time. Barrier height ranged from 0.74 to 0.78 eV was obtained which is in disagreement with simple theory of Schottky. Rapid thermal annealing under optimum conditions leads to a decrease in the Ø Bn which is in good agreement with the expectations. Results of ideality factor for Bi-nSi re- vealed that the thermionic emission current is not dominant through this junction. 1. Introduction The investigation of rectifying metal-semiconductor contacts (Schottky diodes) is still in the current interest for most elemental and compound semiconductors [1–3]. In general, Schottky barrier diodes (SBDs) are of interest as the least complex power device and are discussed as an alternative for p-n junctions [4,5]. They have very fast switching times with no reverse recovery current, because they work with only majority carriers. So SBDs play an important role in the performance of semiconductor devices for various electronics and optoelectronic applications. In recent years, Si Schottky diodes have received much attention due to their maximum potential for heigh power devices in novel band engineering heterostructure devices [6–8]. Metalloid-semiconductor junctions (e.g. Bi-Si, Sb-Si) behave like- MS junctions; the degree of such similarity is yet to be fully established. Tang and Freeman and Qiant et al. [9,10] studied the structure of Bi/(001)Si interface. Oberafo and Ziriki [11,7] showed the possibility of junction formation between Bi or Sb and p-(100)Si, their results revealed that the barrier height is very sensitive to the SiO 2 layer. According to Schottky-Mott model, the barrier height of Bi–nSi contact should be 0.19 eV. However, preparation method could have a major infuence on the value of barrier height – including deposition rate, metal flm thickness, and annealing conditions. Previous work showed that rapid thermal annealing can cause a signifcant impact on the performance of silicon junctions [12]. Little experimental data on the barrier height of Bi–nSi contact are available in literature. In this study, several methods were adopted for the determination of the barrier height. Rapid thermal annealing was performed to study its efect on the barrier height. https://doi.org/10.1016/j.ijleo.2019.05.028 Received 7 March 2019; Accepted 11 May 2019 ⁎ Corresponding author. E-mail address: raidismail@yahoo.com (R.A. Ismail). Optik - International Journal for Light and Electron Optics 188 (2019) 46–51 0030-4026/ © 2019 Elsevier GmbH. All rights reserved. T