Plasmonic photodetectors based on asymmetric nanogap electrodes

Abstract

Hot-electron-based solar energy conversion with metal-semiconductor nanodiodes Young Keun Lee, Hyosun Lee, Changhwan Lee et al. Advances in graphene-based optoelectronics, plasmonics and photonics Bich Ha Nguyen and Van Hieu Nguyen Photoresponse Enhancement in Graphene/Silicon Infrared Detector by Controlling Photocarrier Collection Xin Tang, Hengkai Zhang, Xiaobing Tang et al. Amplification of hot electron flow by the surface plasmon effect on metal-insulator-metal nanodiodes Changhwan Lee, Ievgen I Nedrygailov, Young Keun Lee et al. Light-matter interaction of 2D materials: Physics and device applicationsHot electrons excited by plasmon resonance in nanostructure can be employed to enhance the properties of photodetectors, even when the photon energy is lower than the bandgap of the semiconductor. However, current research has seldom considered how to realize the efficient collection of hot electrons, which restricts the responsivity of the device. In this paper, a type of plasmonic photodetector based on asymmetric nanogap electrodes is proposed. Owing to this structure, the device achieves responsivities as high as 0.45 and 0.25 mA/W for wavelengths of 1310 and 1550 nm, respectively. These insights can aid the realization of efficient plasmon-enhanced photodetectors for infrared detection.

Sub‐Picosecond Nanodiodes for Low‐Power Ultrafast Electronics

“…Recently developed adhesion lithography [ 38–44 ] is generally used to produce coplanar material‐asymmetric nanogaps in geometrically symmetric side‐to‐side form, suffering from restricted materials and larger than 10 nm gap spacing. The direct electron‐beam lithography (EBL) [ 54 ] could enable coplanar geometrically asymmetric nanostructure but compromise significant limitations in terms of low‐throughput, poor scalability to large area and rough boundaries. Here, a novel fabrication process developed from our reported technique [ 55–57 ] is demonstrated to fabricate coplanar asymmetric tip‐to‐edge metal nanostructure with sub‐10 nm air channel and different tip‐to‐edge height.…”

Status and Outlook of Metal–Inorganic Semiconductor–Metal Photodetectors

“…Thus, the wide bandgap semiconductor materials cannot be applied in the fields of fiber optical communication and infrared detection. [ 285 ] Such limitation can be overcome by using subwavelength metallic structures that can excite SPs, thereby inducing a large amount of hot carriers. [ 45,46,286 ] This enables the infrared photodetection based on MSM‐PDs consisting of wide bandgap materials.…”

“…Both 1D and 2D metallic gratings can be used as the electrodes of MSM‐PDs. [ 50,285 ] Initially, the hot carrier photodetectors were developed within the single Schottky‐contact type PDs. [ 287–291 ] In 2013, Knight and co‐workers demonstrated a Schottky‐contact type Si MSM‐PD with a top Au electrode in the form of a plasmonic grating.…”

“…simulated a planar Si MSM‐PD with metal electrodes based on nanofingers with asymmetrical gaps. [ 285 ] Through geometrical optimization, they achieved a responsivity of 0.45 and 0.25 mA W −1 at 1310 and 1550 nm, respectively. Similar simulation works were also performed by other groups.…”

High-Throughput Fabrication of Ultradense Annular Nanogap Arrays for Plasmon-Enhanced Spectroscopy

“…Owing to its superior ability to significantly enhance the field strength and small size, nanogap has become an important element for construction of nanodevices for plasmonics, − molecular sensing, − photoelectronics, memorizers, , THz science, − and metamaterials. , The challenge is to utilize its full potential for integrated applications, for example, on-chip integrated circuits. In the recent years, a variety of methods, such as electron beam lithography, − focused ion beam etching (IBE), electromigration, break junction, , edge lithography, , angled deposition, and chemical synthesis, ,− have been employed to fabricate different nanogaps, although the controllability for making sub-10 nm gaps remains a challenge.…”