Bi (Fe, Zn) O3/NiO all-oxide thin film heterojunction used for high-speed photoelectric detection

Abstract

The invention provides a full-oxide thin film heterojunction based on a zinc-doped bismuth ferrite / nickel oxide material, and belongs to the technical field of semiconductor devices. The invention discloses a method for accurately preparing a zinc-doped bismuth ferrite / nickel oxide thin film heterojunction. The heterojunction adopts a sol-gel technology, the stoichiometric ratio of elements in each layer can be accurately controlled, meanwhile, good crystallinity and uniform and compact morphology of each layer of thin film are ensured, the controllability is strong, the process is simple, and the preparation efficiency is high. Good matching and coupling of zinc-doped bismuth ferrite and nickel oxide are achieved, the heterojunction structure is formed, a bismuth ferrite polarization electric field and a heterojunction built-in electric field are combined to promote photon-generated carrier transport, a high-speed photoelectric response characteristic within a visible light range is obtained, and the heterojunction can be used for manufacturing related semiconductor photoelectric detectors. The heterojunction is of great significance to the practical application of the oxide perovskite thin film in the field of semiconductor devices.

Description

technical field [0001] The invention belongs to the technical field of semiconductor optoelectronic devices, and relates to a Zn-BiFeO3 / NiO thin film heterojunction based on full oxide. Background technique [0002] The outstanding advantage of ferroelectric materials in the fields of photoelectric conversion and photodetection is that the internal electric field generated by spontaneous polarization can improve the separation efficiency of photogenerated excitons and promote carrier transport, thereby improving conversion efficiency and photoelectric response rate. BiFeO 3 (BFO) is one of the few multiferroic materials at room temperature, which exhibits R3c ferroelectric trigonal phase and G-type antiferromagnetic structure at room temperature. The band gap (2.7eV) of BFO is smaller than that of most perovskite oxides, and it is very suitable for preparing clean and stable functional semiconductor devices due to its multiferroic properties at room temperature and its non-...

AI Technical Summary

Problems solved by technology

[0003] In order to further improve the photodetection performance of BFO in the visible light range, two bottlenecks must be solved: ①BFO’s band gap is too large, which is not conducive to the absorption and conversion of visible light; ②BFO is easy to form oxygen vacancies and the variable valence state of iron ions ( From Fe 3+ to Fe 2+ ), leading to a higher recombination rate of photogenerated electrons-holes, thus restricting the response speed

It can be seen that the photoelectric response speed of the above devices still needs to be improved; the charge transport layer of nanomaterials or organic materials coupled with BFO will reduce the structural stability and is not conducive to subsequent device integration

[0006] In summary, there is no research on heterojunction photodetection devices constructed by combining Zn-doped BFO and inorganic oxide charge transport materials.

Images