In this report, we proposed and simulated a new planar nonlinear rectifying device fabricated using InGaAs substrate and referred to as a planar barrier diode (PBD). Using an asymmetrical inverse-arrowhead-shaped structure between the electrodes, a nonuniform depletion region is developed, which creates a triangular energy barrier in the conducting channel. This barrier is voltage dependent and can be controlled by the applied voltage across the PBD, thus resulting in nonlinear diode-like current–voltage characteristics; thus it can be used as a rectifying device. The PBD’s working principle is explained using thermionic emission theory. Furthermore, by varying the PBD’s geometric design, the asymmetry of the current–voltage characteristics can be optimized to realize superior rectification performance. By employing the optimized structural parameters, the obtained cut-off frequency of the device was approximately 270 GHz with a curvature coefficient peak of 14 V ⁻¹ at a low DC bias voltage of 50 mV.

A unipolar two-terminal nanodevice, known as the self-switching diode (SSD), has recently been demonstrated as a room-temperature rectifier at microwave and terahertz frequencies due to its nonlinear current-voltage characteristic. The planar architecture of SSD not only makes the fabrication process of the device faster, simpler and at a lower cost when compared with other rectifying diodes, but also allows the use of various materials to realize and fabricate SSDs. This includes the utilization of ‘green’ materials such as organic and graphene thin films for environmental sustainability. This paper reviews the properties of current ‘green’ SSD rectifiers with respect to their operating frequencies and rectifying performances, including responsivity and noise-equivalent power of the devices, along with the applications.

A planar nanodevice, known as the self-switching diode (SSD), has a nonlinear current-voltage (I-V) characteristic which can be exploited as a high-speed rectifier in a wide range of applications. This diode-like I-V behaviour is achieved due to the structure of the device which consists of an asymmetric nanochannel. In this work, the rectification properties of silicon-based SSDs with different geometry of the nanochannel were reported. The characterization have been performed by means of ATLAS device simulator. The results obtained can be used to facilitate in improving the rectifying performance of the device.

In the advancement of the Internet of Things (IoT) applications, widespread uses and applications of devices require higher frequency connectivity to be explored and exploited. Furthermore, the size, weight, power and cost demands for the IoT ecosystems also creates a new paradigm for the hardware where improved power efficiency and efficient wireless transmission needed to be investigated and made feasible. As such, functional microwave detectors to detect and rectify the signals transmitted in higher frequency regions are crucial. This paper reviewed the practicability of self switching diodes as Radio Frequency (RF) rectifiers. The existing methods used in the evaluation of the rectification performance and cut-off frequency are reviewed, and current achievements are then concluded. The works reviewed in this paper highlights the functionality of SSD as a RF rectifier with design simplicity, which may offer cheaper alternatives in current high frequency rectifying devices for application in low-power devices.

Characterization on an InGaAs-based self-switching diode (SSD) aimed for rectification application at high frequencies is reported. Simulation on the current-voltage (I-V) characteristic of L-shaped 70 nm channel SSD has been conducted using ATLAS two-dimensional (2D) simulator for different insulating channel materials with relative permittivity ranging from 1.0 to 9.3 under temperature range of 300 K-600 K. A similar I-V curve to diode behavior has been observed. Furthermore, the curvature co-efficient of the SSD has been evaluated by extrapolating the simulated I-V graphs and the effects of both permittivity and temperature to the rectification properties are observed. The results obtained can assist the design of SSD to efficiently operate as microwave rectifier, especially in radio frequency harvesting application.