Electrical response of electron selective atomic layer deposited TiO2-x heterocontacts on crystalline silicon substrates

Ahiboz D., Nasser H., Aygun E., Bek A., Turan R.

SEMICONDUCTOR SCIENCE AND TECHNOLOGY, vol.33, no.4, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 33 Issue: 4
  • Publication Date: 2018
  • Doi Number: 10.1088/1361-6641/aab535
  • Journal Name: SEMICONDUCTOR SCIENCE AND TECHNOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: oxygen deficient titanium dioxide, atomic layer deposition, interfaces, electron selective layers, electrical characteristics, OPTICAL-PROPERTIES, TITANIUM-DIOXIDE, CONTACTS
  • Middle East Technical University Affiliated: Yes

Abstract

Integration of oxygen deficient sub-stoichiometric titanium dioxide (TiO2-x) thin films as the electron transporting-hole blocking layer in solar cell designs are expected to reduce fabrication costs by eliminating high temperature processes while maintaining high conversion efficiencies. In this paper, we conducted a study to reveal the electrical properties of TiO2-x thin films grown on crystalline silicon (c-Si) substrates by atomic layer deposition (ALD) technique. Effect of ALD substrate temperature, post deposition annealing, and doping type of the c-Si substrate on the interface states and TiO2-x bulk properties were extracted by performing admittance (C-V, G-V) and current-voltage (J-V) measurements. Moreover, the asymmetry in C-V and J-V measurements between the p-n type and n-n TiO2-x-c-Si heterojunction types were examined and the electron transport selectivity of TiO2-x was revealed.