Self-Powered Broadband Photodetector Based on Single-Walled Carbon Nanotube/GaAs Heterojunctions

Abstract

Van der Waals (vdW) heterojunctions between single-walled carbon nanotubes (SWCNTs) and GaAs are potential candidates for optoelectronic devices owing to their direct bandgap, high carrier mobility, diffusion-free atomically sharp interface, and flexible device structures. The existence of mixed-chirality SWCNTs suppresses the charge separation and transportation of photoexcited carriers at the interface. Herein, we demonstrate a self-powered broadband photodetector by combining n-type GaAs with a (6, 5)-enriched semiconducting SWCNT film. The experimental results show that the device exhibits a broadband photoelectric response spectrum from visible (405 nm) to near-infrared (1064 nm). Under 780 nm illumination, a high responsivity of 274 mA W–1 and detectivity of 7.6 × 1012 Jones can be achieved with a response/recovery time of 1.41/0.27 ms at zero bias. The photoelectric performance is mainly attributed to the enhanced separation efficiency of the photoexcited carriers due to the formation of vdW heterojunctions. Our findings open up the opportunities for highly sensitive self-powered photodetectors.

A high-performance photodetector based on small-bundled single-wall carbon nanotube film/silicon heterojunctions

“…7,52 Furthermore, the D * value in our work is 5 ∼ 10 times higher than those previously reported with a similar device structure. 19,49…”

“…47 The maximum photocurrent reached $0.43 A W À1 at a laser wavelength of 890 nm, much higher than the previously reported values for CNT heterojunction photodetectors with a similar detection area. 19,[49][50][51] Furthermore, this value is roughly equivalent to that of a ve-nger-interdigitated-electrode device with an adjacent electrode distance of 250 mm. 23 We also calculated the wavelength dependence of the NEP and D* based on the R curve shown in Fig.…”

“…10,13,14 The photodetectors based on SWCNT heterojunctions with the advantage of efficient charge separation and transfer have demonstrated desirable optoelectronic detection performance. [15][16][17][18][19][20] Many types of heterojunctions, including SWCNT/ bulk semiconductors, 16,19 SWCNT/nanostructures, 17,18 and SWCNT-based van der Waals 15,20,21 heterojunctions have been developed. SWCNT/bulk semiconductor heterostructures can be constructed by simply transferring SWCNTs onto the surface of a bulk semiconductor, which greatly simplies the traditional heterojunction-forming process.…”

Single-Walled Carbon Nanotube-Germanium Heterojunction for High-Performance Near-Infrared Photodetector

“…The rise time defined as the time interval for the current rising from 10% to 90% of its peak value is 7 µs, and the recovery time defined reversely is 10 µs. This response speed is much quicker than most nanomaterials-based photodetectors [41][42][43].…”

Solution-Processed SnSe2–RGO-Based Bulk Heterojunction for Self-Powered and Broadband Photodetection

“…Therefore, self-powered nanodevices, which can operate without any external power source, have recently gained a lot of attraction. Self-powered PDs − work on a built-in interfacial voltage, which facilitates the separation of the photogenerated electron–hole pairs and leads to the generation of the photocurrent in the external circuit.…”