Aluminum/fluorine-codoped zinc oxide (AFZO) thin films were prepared on silicon and glass substrates through atomic layer deposition at 150 °C. Their structural, electrical, and optical properties were investigated as functions of the F/Al codoping ratio. The X-ray diffraction analysis revealed that the preferred growth orientation changed depending on the codoping with F, that is, from (0 0 0 2) for Al-doped ZnO (AZO) films to (1 0 1 0) for the AFZO ones. The electrical resistivity of the AFZO films (around 5.0 × 10–4 Ω∙cm) was lower than that of the AZO ones; this was mainly attributed to an increase in the n-type carrier concentration (from 4.11 × 1020 cm3 for AZO to 5.86 × 1020 cm3 for AFZO) due to the substitution of the Zn and O sublattice sites by, respectively, the Al and F atoms. The enhanced carrier concentration affected also the optical property of the AFZO films according to the Moss–Burstein shift. The carrier mobility was similarly improved (from 6.96 cm2/V∙s for AZO to 21.2 cm2/V∙s for AFZO) by the passivation of the oxygen vacancies via the F-doping.
Bibliographical noteFunding Information:
This material is based upon work supported by the Ministry of Trade, Industry & Energy (MOTIE, Korea) under Industrial Strategic Technology Development Program. No. 10068075 , 'Development of Mott-transition based forming-less non-volatile resistive switching memory & array' and also supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2019R1A2C2087604 ). Experiments at PLS were supported in part by MEST and POSTECH.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films