Dual-band MgZnO ultraviolet photodetector integrated with Si

Abstract

We have constructed a dual-band ultraviolet photodetector by growing high quality MgxZn1−xO layers on Si substrate with molecular beam epitaxy. The device performance was studied by current-voltage, capacitance-voltage, spectra photoresponse, and time-resolved photoresponse characterizations. It demonstrates a high UV/visible light rejection ratio of more than 2 orders of magnitude and a fast response speed of less than 100 ms. The cutoff wavelength can be at solar-blind (280 nm)/visible-blind (301 nm) region by applying 1 V forward/2 V reverse bias. The working principle of the dual-band photodetector was finally investigated by interpretation of the specific carrier transport behavior with the energy band diagram.

Metal–semiconductor–metal UV photodetector based on Ga doped ZnO/graphene interface

“…It is noticed that the obtained results are better than those of previously reported ZnO thin films based MSM PDs [27,28]. Furthermore, the fabricated device revealed superior responsivity to those of the reported UV PDs, such as graphene/p-Si PDs, mixed-phase ZnMgO based PDs and dual band MgZnO UV PDs integrated on Si [25,29,30]. The fact that PD response dropped from 48.37 at 0.32 A/W at wavelength 350-400 nm across the cut-off region also indicates that high quality ZnO:Ga thin film is grown on graphene/SiO 2 /Si.…”

“…I-V characteristics of the ZnO:Ga/graphene MSM PDs is analyzed by thermionic emission theory to calculate electrical parameters using the following diode equations [25] …”

Energy band bowing parameter in MgZnO alloys

“…Ternary semiconducting crystals are interesting because it is possible to smoothly change many important physical properties by varying their composition. [1][2][3][4] In particular, the MgZnO alloy system covers a wide ultraviolet (UV) spectral range between the direct bandgaps of $3.37 eV for ZnO and $7.8 eV for MgO at room temperature, and is very attractive for short-wavelength optical applications such as UV detectors and UV light emitters. 5,6 MgZnO alloys with different bandgap energies can be used to form ZnO/MgZnO or MgZnO/MgO multilayer quantum wells (QWs) heterostructure in UV light emitting diodes and laser diodes.…”

Photoelectric characteristics of the p–n junction between ZnO nanorods and polyaniline nanowires and their application as a UV photodetector

“…With a wide direct band gap of 3.37 eV and a large 2 exciton binding energy of 60 meV, ZnO nanostructure has been widely investigated and exhibited potential applications for UV photodetectors [5][6][7][8]. The photodetectors with various types and shapes of ZnO have been investigated by many research groups [9][10][11][12][13].…”