Graphene Interdigital Electrodes for Improving Sensitivity in a Ga₂O₃:Zn Deep-Ultraviolet Photoconductive Detector

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Graphene (Gr) is a promising transparent electrode material for photodetectors due to its conductivity and transmittance.
• Current limitations in graphene manipulation hinder the practical application and arraying of photodetectors.

Purpose of the Study:

• To develop an efficient method for tailoring graphene into interdigital electrodes.
• To fabricate a sensitive and stable deep-ultraviolet (DUV) photodetector using Zn-doped Ga2O3 films and patterned graphene electrodes.

Main Methods:

• A multistep method was employed to accurately pattern graphene into interdigital electrodes.
• Fabrication of a deep-ultraviolet photodetector utilizing Zn-doped Ga2O3 films and tailored graphene electrodes.

Main Results:

• The fabricated photodetector demonstrated extremely low dark current (~10^-11 A) and an ultrahigh photo-to-dark ratio (>10^5).
• Satisfactory responsivity (1.05 A/W) and excellent selectivity for the deep-ultraviolet band were achieved.
• Performance improvements are attributed to increased photon incidence via graphene and carrier separation by the built-in electric field at the graphene/Ga2O3:Zn interface.

Conclusions:

• The proposed graphene tailoring technique significantly enhances photodetector performance.
• This method contributes to the practical development and application of graphene in optoelectronic devices.