Metal–Semiconductor–Metal Ultraviolet Photodetectors Based on Al Nanoparticles in 4H-SiC Microholes
Meng Yuan, Mingkun Zhang, Zhao Fu, Shan Han, Yuning Zhang, Shaoxiong Wu, Rongdun Hong, Xiaping Chen, Jiafa Cai, Dingqu Lin, Zhengyun Wu, Baoping Zhang, Jicheng Wang, Feng Zhang
Abstract
A significant ultraviolet (UV) detection enhancement is realized by etching microhole (MH) arrays and localized surface plasmon resonance (LSPR) of Al nanoparticles (NPs) on 4H-SiC metal–semiconductor–metal (MSM) photodetectors (PDs). 4H-SiC PDs with different diameters of MHs are fabricated, which exhibit an ultralow dark current of approximately 5.0 × 10 –15 A at 5 V bias. The PD with 3 μm MH exhibits the best performance, and its peak responsivity is 35% higher than that of device without MH. The peak responsivity of PDs with both 3 μm MH and NPs enhanced nearly 6 times that without Al NPs. The PD with both 3 μm MH and Al NPs indicates the best detection performance, with a maximum detectivity of 4.0 × 10 13 Jones at 270 nm, which is nearly an order of magnitude higher than devices without Al NPs. The fabricated MH and Al NPs MSM PDs have a high response on the order of nanoseconds, with a rise/decay time of 2.1 ns/2.5 ns at 5 V bias. The complementary optical properties of MH and Al NPs with 4H-SiC can promote the development and application of high-performance UV PDs.