Junction‐Enhanced Polarization Sensitivity in Self‐Powered Near‐Infrared Photodetectors Based on Sb₂Se₃ Microbelt/n‐GaN Heterojunction

Abstract

Polarization‐sensitive photodetectors (PDs) based on anisotropic materials spark considerable interest for their potential applications in security surveillance, optical switches, and remote sensing. However, high‐thickness or bulk anisotropic materials generally exhibit low polarization sensitivity, hindering their practical applications in polarization photodetection. Herein, a near‐infrared (NIR) PD based on a p‐type Sb2Se3 microbelt (MB)/n‐GaN heterojunction is proposed. The Sb2Se3 MB/GaN PD effectively combines the anisotropy of the Sb2Se3 MB with the heterogeneous integration. The PD presents self‐powered detection properties with a responsivity over 12 mA W−1, a specific detectivity exceeding 5 × 1010 Jones, and a response speed (the rising/decaying times ≈74 ms/75 ms) under NIR illumination. More importantly, the heterojunction‐based PD has a higher anisotropy ratio of 1.37, which is 1.3 times amplified as compared to the vertical photoconductive‐type PDs (the anisotropy ratio of 1.06). The p‐n junction's effect on carrier generation and recombination causes the increased polarization sensitivity of Sb2Se3 MB/GaN PDs, as confirmed by finite element method analysis. This work not only offers a deeper insight into polarization sensitivity regulated by junction or interface but also provides a practical method for developing high‐sensitivity polarization detectors based on high‐thickness or bulk anisotropic materials.

Quantum tailoring for polarization-discriminating Bi2S3 nanowire photodetectors and their multiplexing optical communication and imaging applications

“…On the whole, the above results have explained the substantial distinction of the dichroic ratios of the previously reported (quasi-)1D material ( e.g. , Te, 76,77 Sb 2 S 3 , 10,78 Sb 2 Se 3 40,75 ) photodetectors, despite the fact that these devices are built of the same kind of materials. This finding may provide a universal navigation for the optimization of the dichroism of polarization-sensitive photodetectors by leveraging quantum tailoring.…”

“…Of note, this value even far exceeds the theoretical dichroic ratio ceiling (≈1.8) of bulk Bi 2 S 3 predicted by a previous study, 37 which suggests the determinant effect of extrinsic quantum tailoring. In addition, the dichroic ratio is competitive among the state-of-the-art polarization-sensitive photodetectors based on various materials, such as KNb 3 O 8 , 64 Sb 2 Se 3 , 11 Bi 1.3 In 0.7 Se 3 , 65 SbBiS 3 , 42 (BA) 2 (FA)Pb 2 I 7 , 66 SnS, 67 In 2 Se 3 , 68 ZrS 3 , 69 SiP 2 , 70 GeS 2 , 71 CrPS 4 , 72 GaPS 4 , 73 and Cs 2 AgBiBr 6 , 74 as well as various heterostructures such as Sb 2 Se 3 /GaN 75 (Fig. S27, ESI†).…”

Flexible self-powered solar-blind Schottky photodetectors based on individual Ga2O3 microwire/MXene junctions

“…34 θ can be estimated as 0.46, which implies that recombination of photo-induced electrons and holes exists in the Ga 2 O 3 MW/MXene photodetector. 35,36 The linearity of the photoresponse can be strengthened further by tactics such as passivating the defective states in the interface and improving the quality of the MXene electrodes. 37…”

Topological Bi2Se3/n-GaN Hybrid Structure for Enhanced and Self-Powered UV Photodetectors

“…They have found the responsivity of pristine ZnO to be ∼0.33 A/W, but it increased to 1.23 A/W at 1 V after the Bi 2 S 3 addition due to the optimum UV absorption and charge separation occurring at the interface . It has been reported by Wan et al that the PD based on the p-type Sb 2 Se 3 microbelt over n-GaN exhibits self-powered detection properties with a responsivity over 12 mA/W in the near-infrared region . Out of several topological insulators, Bi 2 Se 3 has a prominent topological insulator (TI) property and has insulation in the bulk with a gapless surface. , The backscattering of carriers on its surface is prevented by the symmetry of time inversion.…”

“…Various efforts have been made to enhance the UV photodetection properties of MSM-based GaN UV PDs. Few researchers have reported the plasmonic enhancement of UV photodetection of GaN PDs using Au, Ag, and Pt nanoparticles because they induce the ‘local surface plasmon resonance (LSPR)’ effect which increases the light absorption efficiency, and hot carriers are injected into the semiconductor, followed by enhancement in the photocurrent. − Furthermore, it is well known that 2D materials have outstanding charge carrier transport and mobility, − and therefore, recently, in a few reports, different 2D materials have been used over WBG semiconductors for the fabrication of PDs. − Also, the 2D material/WBG semiconductor hybrid structure develops a built-in electric field that is capable of increasing the separation of photogenerated charge carriers and diminishing the recombination rate. As a result, the lifetime of photogenerated free charge carriers enhances, which improves the speed and response of the PD device.…”