Memristors are now becoming a prominent candidate to serve as the building blocks of non-von Neumann in-memory computing architectures. By mapping analog numerical matrices into memristor crossbar arrays, efficient multiply accumulate operations can be performed in a massively parallel fashion using the physics mechanisms of Ohm’s law and Kirchhoff’s law. In this brief review, we present the recent progress in two niche applications: neural network accelerators and numerical computing units, mainly focusing on the advances in hardware demonstrations. The former one is regarded as soft computing since it can tolerant some degree of the device and array imperfections. The acceleration of multiple layer perceptrons, convolutional neural networks, generative adversarial networks, and long short-term memory neural networks are described. The latter one is hard computing because the solving of numerical problems requires high-precision devices. Several breakthroughs in memristive equation solvers with improved computation accuracies are highlighted. Besides, other nonvolatile devices with the capability of analog computing are also briefly introduced. Finally, we conclude the review with discussions on the challenges and opportunities for future research toward realizing memristive analog computing machines.

Heart rate variability (HRV) that can reflect the dynamic balance between the sympathetic nervous and parasympathetic nervous of human autonomic nervous system (ANS) has attracted considerable attention. However, traditional electrocardiogram (ECG) devices for HRV analysis are bulky, and hard wires are needed to attach measuring electrodes to the chest, resulting in the poor wearable experience during the long-term measurement. Compared with that, wearable electronics enabling continuously cardiac signals monitoring and HRV assessment provide a desirable and promising approach for helping subjects determine sleeping issues, cardiovascular diseases, or other threats to physical and mental well-being. Until now, significant progress and advances have been achieved in wearable electronics for HRV monitoring and applications for predicting human physical and mental well-being. In this review, the latest progress in the integration of wearable electronics and HRV analysis as well as practical applications in assessment of human physical and mental health are included. The commonly used methods and physiological signals for HRV analysis are briefly summarized. Furthermore, we highlighted the research on wearable electronics concerning HRV assessment and diverse applications such as stress estimation, drowsiness detection, etc. Lastly, the current limitations of the integrated wearable HRV system are concluded, and possible solutions in such a research direction are outlined.

Superjunction technology is believed to reach the optimal specific on-resistance and breakdown voltage trade-off. It has become a mainstream technology in silicon high-voltage metal oxide semiconductor field effect transistor devices. Numerous efforts have been conducted to employ the same concept in silicon carbide devices. These works are summarized here.

Two-dimensional (2D) bismuth, bismuthene, is an emerging pnictogen family member that has received increasing research attention in the past few years, which could yield exotic electrical, thermal, and optical properties due to unique band structure. This review provides a holistic view of recent research advances on 2D bismuth material synthesis and device applications in complementary metal oxide semiconductor (CMOS) technology. Firstly, the atomic and band structure of bismuthene is reviewed as the fundamental understanding of its physical properties. Then, it highlights material synthesis of 2D bismuth atomic sheets with emphasis on physical vapor deposition method with accurate layer controllability and process compatibility with CMOS technology. Moreover, it will survey latest applications of 2D bismuth in terms of electronic, optic, thermoelectric, spintronic and magnetic nanodevices. 2D bismuth derivatives (Bi–X, X = Sb, Te, Se) will also be mentioned as a promising strategy to further improve device performance. At last, it concludes with a brief summary on the current challenges and future prospects in 2D bismuth and its derivatives for innovative electronics, sensors and other devices compatible with CMOS techniques.

We present a new approach based on the multi-trench technique to improve the electrical performances, which are the fill factor and the electrical efficiency. The key idea behind this approach is to introduce a new multi-trench region in the intrinsic layer, in order to modulate the total resistance of the solar cell. Based on 2-D numerical investigation and optimization of amorphous SiGe double-junction (a-Si:H/a-SiGe:H) thin film solar cells, in the present paper numerical models of electrical and optical parameters are developed to explain the impact of the multi-trench technique on the improvement of the double-junction solar cell electrical behavior for high performance photovoltaic applications. In this context, electrical characteristics of the proposed design are analyzed and compared with conventional amorphous silicon double-junction thin-film solar cells.

In DSP-based SerDes application, it is essential for AFE to implement a pre-ADC equalization to provide a better signal for ADC and DSP. To meet the various equalization requirements of different channel and transmitter configurations, this paper presents a 112 Gbps DSP-Based PAM4 SerDes receiver with a wide band equalization tuning AFE. The AFE is realized by implementing source degeneration transconductance, feedforward high-pass branch and inductive feedback peaking TIA. The AFE offers a flexible equalization gain tuning of up to 17.5 dB at Nyquist frequency without affecting the DC gain. With the proposed AFE, the receiver demonstrates eye opening after digital FIR equalization and achieves 6 × 10⁻⁹ BER with a 29.6 dB insertion loss channel.

A high-performance single-pole single-throw (SPST) RF switch for mobile phone RF front-end modules (FEMs) was designed and characterized in a 0.13 μm partially depleted silicon-on-insulator (PD SOI) process. In this paper, the traditional series-shunt configuration design was improved by introducing a suitably large DC bias resistor and leakage-preventing PMOS, together with the floating body technique. The performance of the RF switch is greatly improved. Furthermore, a new R_on × C_off testing method is also proposed. The size of this SPST RF switch is 0.2 mm². This switch can be widely used for present 4G and forthcoming 5G mobile phone FEMs.

In this work, a PEDOT:PSS/Sn:α-Ga₂O₃ hybrid heterojunction diode (HJD) photodetector was fabricated by spin-coating highly conductive PEDOT:PSS aqueous solution on the mist chemical vapor deposition (Mist-CVD) grown Sn:α-Ga₂O₃ film. This approach provides a facile and low-cost p-PEDOT:PSS/n-Sn:α-Ga₂O₃ spin-coating method that facilitates self-powering performance through p−n junction formation. A typical type-Ⅰ heterojunction is formed at the interface of Sn:α-Ga₂O₃ film and PEDOT:PSS, and contributes to a significant photovoltaic effect with an open-circuit voltage (V_oc) of 0.4 V under the 254 nm ultraviolet (UV) light. When operating in self-powered mode, the HJD exhibits excellent photo-response performance including an outstanding photo-current of 10.9 nA, a rapid rise/decay time of 0.38/0.28 s, and a large on/off ratio of 91.2. Additionally, the HJD also possesses excellent photo-detection performance with a high responsivity of 5.61 mA/W and a good detectivity of 1.15 × 10¹¹ Jones at 0 V bias under 254 nm UV light illumination. Overall, this work may explore the potential range of self-powered and high-performance UV photodetectors.

The random nanofiber distribution in traditional electrospun membranes restricts the pressure sensing sensitivity and measurement range of electronic skin. Moreover, current multimodal sensing suffers from issues like overlapping signal outputs and slow response. Herein, a novel electrospinning method is proposed to prepare double-coupled microstructured nanofibrous membranes. Through the effect of high voltage electrostatic field in the electrospinning, the positively charged nanofibers are preferentially attached to the negatively charged foam surface, forming the ordered two-dimensional honeycomb porous nanofibrous membrane with three-dimensional spinous microstructure. Compared with the conventional random porous nanofibrous membrane, the bionic two-dimensional honeycomb and three-dimensional spinous dual-coupled microstructures in the ordered porous nanofibrous membrane endows the electronic skin with significantly improved mechanical properties (maximum tensile strain increased by 77% and fatigue resistance increased by 35%), air permeability (water vapor transmission rate increased by 16%) and sensing properties (pressure sensitivity increased by 276% and detection range increased by 137%). Furthermore, the electronic skin was constructed by means of a conformal composite ionic liquid functionalized nanofibrous membrane, and the real-time and interference-free dual-signal monitoring of pressure and temperature (maximum temperature coefficient of resistance: −0.918 °C⁻¹) was realized.