This paper reports the first successful fabrication of an ITO/silkworm hemolymph/Al bio-memristor using silkworm hemolymph as the active layer. Experiments demonstrate that the silkworm hemolymph bio-memristor is a nonvolatile rewritable bipolar memory device with a current switching ratio exceeding 103. The state of the bio-memristor can be retained for more than 104 seconds and remains stable for at least 500 cycles. Tests of 1/f noise have shown that the resistance switching characteristics of the silkworm hemolymph bio-memristor are related to the formation and breaking of conductive filaments, which result from the migration of oxygen ions and the oxidation and reduction of metal cations in the silkworm hemolymph film. The naturally non-toxic silkworm hemolymph offers advantages for human health, environmental protection, and biocompatibility. The proposed nonvolatile rewritable bio-memristor based on silkworm hemolymph possesses great application potential.

Logic gate functions built with nonvolatile resistive switching and thermoresponsive memory based on biologic proteins were investigated. The “NAND” and “NOR” functions of logic gates in soya protein devices have been built at room temperature by their nonvolatile ternary WORM resistive switching behaviors. Furthermore, heating the devices from room temperature to 358 K results in a switch from tristable state to bistable state WORM resistive switching behavior, indicating that the thermoresponsiveness can be efficiently memorized. The biologic transient nonvolatile memory device consisting of soya protein is illustrated. This device exhibits a long data retention time (104 s) and significant HRS/LRS ratio (∼105); the transient response of the current to voltage of an as-fabricated device is also explored. The soya protein based memory device on a gelatin film substrate is also assessed to validate the feasibility of degradation and biological compatibility for the implantable biological electronic device, that is, innoxious and avirulent to the human body. This can offer alternative avenues for exploring prospective bioelectronic devices.

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Nonvolatile ternary memory devices were fabricated using the composite of polystyrene (PS) and graphene oxide(GO) as active layers, which have an reliable intermediate state. The current-voltage (I-V) curves of the indium tin oxide (ITO)/PS+GO/Al device under the external applied voltages exhibited current tri-stability with three conductivity states, which clearly revealed ternary memory performance. Under the stimulus of the external voltage, a stable intermediate conductivity state was observed. In the write-read-erase-read test, the ITO/PS+GO/Al device exhibited rewritable, nonvolatile, ternary memory properties. The resistance as functions of the time indicated that three conductivity states held for 2 × 105 s, suggesting that the good stability of the ITO/PS+GO/Al devices. HRTEM and XPS observation indicated that the Al top electrode reacted with oxygen within in GO.

Nonvolatile ternary memory devices were fabricated from the composites polymer blends containing zinc oxide (ZnO) nanoparticles. When applying a negative bias on the top electrode, the fabricated devices with a simple sandwich structure of indium tin oxide (ITO)/composite polymer/aluminum (Al) exhibited three distinct resistance states, which could be labeled as "OFF", "ON1" and "ON2" for ternary data storage application. The ITO/polystyrene (PS) + ZnO/Al devices can endure 3 × 10 read-cycles and exhibit a retention time of 10 s. The resistance-temperature dependence at different resistance states was investigated to confirm the temperature-dependent properties. The resistance of the "OFF" and "ON1" state reveals negative temperature dependence, manifesting a typical semiconductor characteristic. The resistance of the "ON2" state exhibits positive temperature dependence, showing metallic properties.

A novel nc-Si/c-Si heterojunction MOSFETs pressure sensor is proposed in this paper, with four p-MOSFETs with nc-Si/c-Si heterojunction as source and drain. The four p-MOSFETs are designed and fabricated on a square silicon membrane by CMOS process and MEMS technology where channel resistances of the four nc-Si/c-Si heterojunction MOSFETs form a Wheatstone bridge. When the additional pressure is P, the nc-Si/c-Si heterojunction MOSFETs pressure sensor can measure this additional pressure P. The experimental results show that when the supply voltage is 3 V, length-width (L:W) ratio is 2:1, and the silicon membrane thickness is 75 μm, the full scale output voltage of the pressure sensor is 15.50 mV at room temperature, and pressure sensitivity is 0.097 mV/kPa. When the supply voltage and L:W ratio are the same as the above, and the silicon membrane thickness is 45 μm, the full scale output voltage is 43.05 mV, and pressure sensitivity is 2.153 mV/kPa. Therefore, the sensor has higher sensitivity and good temperature characteristics compared to the traditional piezoresistive pressure sensor.

A two-dimensional (2D) magnetic field sensor consisting of four silicon magnetic sensitive transistors (SMSTs) with similar characteristics is presented in this paper. By use of micro-electromechanical systems (MEMS) and integrated packaging technology, this sensor fabricated by using the silicon wafer with a <100> orientation and high resistivity, was packaged on printed circuit boards (PCBs). In order to detect the magnetic fields in the x and y axes directions, two of the four SMSTs with opposite magnetic sensitive directions were located along the x and −x axes directions, symmetrically, and the others were located along the y and −y axes directions. The experimental results show that when the VCE = 10.0 V and IB = 6.0 mA, the magnetic sensitivities of the sensor in the x and y axes directions are 366.0 mV/T and 365.0 mV/T, respectively. It is possible to measure the 2D magnetic field and improve the magnetic sensitivity, significantly.

PSS composite thin films, the electrical conductance switching behavior of ITO/PEDOT:PSS + SWCNTs/Al can be modulated in a controlled manner.