Abstract

An enhanced spectral response was realized in an AlGaN-based solar-blind ultraviolet (SB-UV) detector using aluminum (Al) nanoparticles (NPs) of 20-60 nm. The peak responsivity of the detector (about 288 nm) with 60 nm Al NPs is more than two times greater than that of a detector without Al NPs under a 5-V bias, reaching 0.288 A/W. To confirm the enhancement mechanism of the Al NPs, extinction spectra were simulated using time-domain and frequency-domain finite-element methods. The calculation results show that the dipole surface plasmon resonance wavelength of the Al NPs is localized near the peak responsivity position of AlGaN-based SB-UV detectors. Thus, the improvement in the detectors can be ascribed to the localized surface plasmon resonance effect of the Al NPs. The localized electric field enhancement and related scattering effect result in the generation of more electron-hole pairs and thus a higher responsivity. In addition, the dark current of AlGaN-based SB-UV detectors does not increase after the deposition of Al nanoparticles. The results presented here is promising for applications of AlGaN-based SB-UV detectors.

Highlights

  • AlGaN-based solar-blind ultraviolet (SB-UV) detectors have attracted much attention because they are in a solid state and small in size, with good chemical and thermal stability, thereby requiring less energy and having a long lifetime

  • An enhanced spectral response was realized in an AlGaN-based solar-blind ultraviolet (SB-UV) detector using aluminum (Al) nanoparticles (NPs) of 20-60 nm

  • The calculation results show that the dipole surface plasmon resonance wavelength of the Al NPs is localized near the peak responsivity position of AlGaN-based SB-UV detectors

Read more

Summary

Introduction

AlGaN-based solar-blind ultraviolet (SB-UV) detectors have attracted much attention because they are in a solid state and small in size, with good chemical and thermal stability, thereby requiring less energy and having a long lifetime. The stringent requirements on crystalline quality, device structure and processing techniques hinder the wide application of avalanche-type SB-UV detectors These detectors work at high voltage and usually suffer from noise. When the frequency ωsp of this collective electron-photon oscillation is close to the frequency of the excitation light wave, resonance occurs, which enables a deep subwavelength localization of incident electromagnetic fields [9,10,11]. Based on this principle, high responsivity in GaN UV detectors has been realized by enhancement with silver (Ag) NPs [12]. The enhancement mechanism is explored and discussed by means of the finite-difference time-domain (FDTD) method based on the quasi-particle approximation

Experimental section
Results and discussion
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.