Investigation On Fabrication And Defects Of P-Type In-N Codoped ZnO Films

As a II-VI direct wide bandgap?3.37 eV?semiconductor material,zinc oxide?ZnO?has an exciton binding energy of 60 meV at room temperature,which is about twice that of GaN?25 meV?.What's more,ZnO also has the advantages of rich raw materials and non-toxicity.Therefore,ZnO has broad application prospects in the fields of light-emitting diodes,lasers,solar cells,gas sensors,ultraviolet detectors and other short-wavelength photovoltaic devices and transparent electrodes.In order to further improve the conductivity of ZnO,Al,Ga,and Indium?In?doping are often used,in which the radius of In³⁺is the closest to the radius of Zn²⁺,and the In doping results in a smaller change in the lattice distortion of ZnO;In addition,In has a large electronegativity and is not as good as Al.Ga,Zn active,it is not easy to form oxides,and it is more conducive to exist in the form of substitutional sites in the crystal lattice to achieve effective doping.At present,In doped ZnO?ZnO:In?thin films can be prepared by various methods.The difference in In content will also have an influence on subsequent doping to achieve p-type conductivity.It is necessary to systematically and thoroughly study the relevant characteristics of ZnO:In films with different In contents.In order to further explore the p-type conductivity mechanism of ZnO,it is possible to solve the problem of p-type conductivity instability.Based on the donor-acceptor co-doping theory,the effects of different annealing temperatures on the structure and electrical properties of In-N co-doped ZnO thin films[ZnO:?In,N?]were investigated.The relationship between the p-type transition mechanism and the intrinsic defect in the thin film was discussed.Through the study,the following results are obtained:1.The ZnO:In films with different In contents were prepared by RF magnetron sputtering technique.The samples exhibited n-type conductivity,and the conductivity was greatly affected by In doping concentration.It was found that within the range of In content in this paper,with the increase of In doping concentration,the electrical properties of the film and the band gap have a change.2.Through the study of thin film Raman and photoluminescence spectra,the content of intrinsic defects in different In content of ZnO:In films is also different.Through system analysis,we can find ZnO:In films that are more suitable for further doping to achieve p-type conductivity.3.In-N co-doped Zn O thin films were prepared on quartz glass substrates by RF magnetron sputtering and ion implantation techniques.Through optimization of the annealing process,a repeatable p-type ZnO:?In,N?thin film with a hole concentration of approximately 10¹⁶ cm^-3 was successfully realized,and an electrical transition phenomenon was observed with annealing.4.Using X-ray diffraction?XRD?X-ray photoelectron spectroscopy?XPS?,Raman spectroscopy and photoluminescence spectroscopy?PL?and other testing methods,the effects of doping impurities and intrinsic defects in ZnO:?In,N?thin films on the structure and p-type conductivity of the thin film were investigated.