Effect of C₄₄H₃₀N₄O₄ Surface Modification on the Performance of Al0.6Ga0.4N MSM Photodetectors

The high defect density on the surface of AlGaN material with high Al composition limits its application in the field of solar-blind ultraviolet (UV) detection. In this work, a surface modification method for AlGaN has been proposed to enhance the performance of AlGaN metal–semiconductor–metal (MSM) solar-blind UV photodetectors (PDs). The 5,10,15,20-T(4-OH P)P (C
₄₄
H
₃₀
N
₄
O
₄
) organic molecules are chemically adsorbed on the surface of high-Al-content Al
_0.6
Ga
_0.4
N MSM PD, which can reduce the interface potential caused by material defects and increase the photogenerated carriers of the device. Compared with the control unmodified PD, the C
₄₄
H
₃₀
N
₄
O
₄
modification method significantly increases the photocurrent and responsivity of the PD, which is beneficial to improve the optoelectronic performances of III-nitride-based PDs.