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Based on an 0.18 μm process, this paper proposes a fully integrated 1.8 V output 300 mA load low-dropout linear regulator (LDO) with a fast transient response. By inserting a transient-enhanced biased Class AB super source follower at the gate of the output power transistor, this LDO can quickly adjust the gate voltage of the power transistor without additional power consumption. By adding an active capacitor circuit composed of a fast comparator with offset voltage at the output point, this LDO can quickly charge/discharge the transient current and accelerate the transient response without reducing the circuit stability. Simulation results show that the proposed LDO has an output voltage of 1.8 V, when the input voltage is 2 V to 5 V while consuming 66.4 μA of quiescent current. The proposed capless LDO has a 1.94 µV/mA load regulation, a 0.55 mV/V linear regulation, and a −60 dB@1 kHz power supply rejection. When the load current steps from 3 mA to 300 mA in 300 ns, the LDO settles in 400 ns with an overshoot and undershoot of 67 mV and 86 mV, respectively. [ABSTRACT FROM AUTHOR]

Radiation effects of a 150 keV proton beam with various fluences on GaN-based quasi-vertical p–i–n diodes are investigated. For fundamental analysis, the electrical properties of P-GaN and N−-GaN separated from p–i–n diodes are also investigated. With the increase in the radiation-induced defect (e.g., VN and VGa) density, the carrier concentrations and mobilities of P-GaN and N−-GaN decrease significantly. Under the proton fluence of 1 × 1015 p/cm2, P-GaN has been transformed into highly resistive N-GaN, resulting in p–i–n diodes losing electrical characteristics of the PN junction. Meanwhile, the P-GaN Ohmic contact has been converted to Schottky contact. In addition, due to a large number of radiation-induced defects in P-GaN and N−-GaN, the reverse leakage current mechanism is revealed to change from space-charge-limited current conduction to Ohmic conduction. [ABSTRACT FROM AUTHOR]

Electrical and optical properties deterioration of P-GaN films under 150 keV proton irradiation were investigated. Through the Hall measurement method, as the irradiation fluence increasing, the carrier concentration of P-GaN films decreases from 1.23 $\times \,\,10^{{17}}$ to $-8.24\,\,\times \,\,10^{{16}}$ cm−3, and the carrier mobility change from 5.64 to 295.84 cm2/V/s. And through the circular transmission line model method, the sheet resistance and specific contact resistance for P-GaN films increased first and then decreased slightly under the proton irradiation. Radiation-induced $\text{V}_{\mathrm {N}}$ , $\text{Ga}_{\mathrm {i}}$ , $\text{V}_{\mathrm {Ga}}$ , and $\text{N}_{\mathrm {i}}$ were found to be responsible for the degradation of P-GaN films. It was confirmed that P-GaN has been transformed into N-GaN under the fluence of 1 $\times \,\,10^{15}$ p/cm2. The optical properties of the P-GaN films were characterized by examining changes in the photoluminescence spectrum. In addition, the electrical characteristics of Schottky barrier diode (SBD) and p-i-n diodes with the same structure (except for 0.5 $\mu \text{m}$ P-GaN of p-i-n diode) were used to study the effect of P-GaN degradation on electronic device performance. When P-GaN was transformed into N-GaN, p-i-n diodes lost the electrical characteristics of the p-n junction and the ${I}$ – ${V}$ curves of p-i-n diode are similar to that with SBD. [ABSTRACT FROM AUTHOR]

This work introduces a current reference with wide temperature operation range and low temperature drift, which can be used in high‐performance intelligent power driver ICs. The core idea of the design is to use the non‐linear characteristics of the drain current of MOSFET working in the sub‐threshold region to realize the compensation of the reference current in low temperature and high‐temperature section, then to reduce the fluctuation of reference current in the whole temperature range (TR). Compared with conventional structures, the temperature drift coefficient of this design is reduced by one order of magnitude. The proposed circuit is designed and verified under a 0.18 μm BCD technology, which occupies a footprint of about 0.085 mm2. Measured data shows that the output reference current at 1 μA has a temperature coefficient of 53.5 ppm/℃ during TR of −40–150℃. [ABSTRACT FROM AUTHOR]

The LiP infinite double-helix chain gives us the unique opportunity to investigate the double-helix structure at atomic level. Based on density-functional theory, we investigate the characteristic vibrational modes of this peculiar structure. Differently from single-wall carbon nanotubes, a dipole mode in LiP gives rise to high infrared intensity. Owing to the peculiar double-helix structure of LiP, the frequency of the out-of-phase radical breathing mode is lower than that of the in-phase one. It is similar to the condition of DNA. Furthermore, the out-of-phase breathing mode in LiP, instead of the in-phase one, has the highest Raman intensity. Most importantly, our finding is generally applicable to other double-helix structures. [ABSTRACT FROM AUTHOR]

In this work, the electrostatic discharge (ESD) characteristics of a pMOS-triggered bidirectional silicon-controlled rectifier (PTBSCR) that was fabricated in a 0.18 μm silicon-on-insulator (SOI) bipolar-CMOS-DMOS (BCD) process, is investigated. The multi-snapback phenomenon was observed under the transmission line pulsing (TLP) test system. It was found that gate voltage and inserting shallow trench isolation (STI) can significantly affect the trigger voltage and holding voltage. The underlying physical mechanism related to the multi-snapback phenomenon and the effects of gate voltage on the critical parameters was investigated through the experimental results and the assistance of technology computer-aided design (TCAD) simulations. The adjustments of gate voltage and STI on the critical ESD parameters of the device provide an effective design idea for low-voltage ESD protection in the SOI BCD process. [ABSTRACT FROM AUTHOR]

An area-efficient clamp based on transmission gate feedback technology is presented for power rail electrostatic discharge (ESD) protection. With this novel design, only a time constant of 10 ns is required for triggering and keeping the clamp turn-on during an ESD event. Full chip ESD protection with this design can endure a human body model pulse of 4500 V. Compared with the conventional clamp with the same area, the proposed clamp has 28% improvement in ESD protection capability. Simulation results show that there is no mistriggering problem caused by power-on pulse and power noise. [ABSTRACT FROM AUTHOR]

Abstract High-performance Zn-Al layered double hydroxide nanosheets-coated spherical ZnO@C composite is successfully fabricated for use as advanced anode materials of zinc-based rechargeable batteries. It is interestingly found that the spherical ZnO@C-ZnAl layered double hydroxide (15%) composite with a proper coated content of ZnAl layered double hydroxide shows a superior cycling performance, satisfactory volume specific capacity and enhanced high-rate properties. After 400 cycles at 1C/1C and 200 cycles at 1C/5C, the ZnO@C-ZnAl layered double hydroxide (15%) exhibits enhanced capacity retention of 81.6%. In contrast, the pristine ZnO shows low capacity retention of only 46.3% after 200 cycles at 1C/1C. These performance improvements can be mainly attributable to the synergistic effect of the surface coating with Zn-Al layered double hydroxide and in-situ doping with carbon. The coated Zn-Al layered double hydroxide nanosheets can modify the"dissolution-deposition" process of ZnO anode and the doped C can enhance its electronic conductivity, eventually leading to the reduced electrochemical resistance, improved reaction reversibility, and enhanced structural stability. As a result, it is believed that the spherical ZnO@C-ZnAl layered double hydroxide (15%) composite is a promising advanced anode material for zinc-based rechargeable batteries. Graphical abstract Image 1 Highlights • Zn-Al-LDHs nanosheets-coated spherical ZnO@C composites were synthesized. • ZnO@C-ZnAl LDHs(15%) shows satisfied cycle stability and high-rate performance. • A new type of Ni-Zn battery with ZnO@C-ZnAl LDHs anode is successfully developed. • The electrochemical reaction process of ZnO@C-ZnAl LDHs anode has been studied. [ABSTRACT FROM AUTHOR]

Abstract In recent years, how to properly recycle increasing spent LiFePO 4 batteries is becoming an extremely thorny subject, which is related to not only a severe environmental pollution but also a serious waste of valuable resources. Here, for the first time, a sustainable and smart approach is established for manufacturing LiFePO 4 /C/FeS composites from spent LiFePO 4 powders as novel anode materials for alkaline Ni-Fe secondary battery. The LiFePO 4 /C/FeS composites are prepared via a facile ball milling method by using spent LiFePO 4 and commercial FeS as raw materials. When serving as host anode material for Ni-Fe battery, the LiFePO 4 /C/FeS (40 wt %) composite exhibits attractive anodic performance in alkaline solution, with a high specific discharge capacity of ～232.9 mAh g−1 (639.1 mAh g−1 Fe) at 0.2C, prominent high-rate capabilities (～150.7 mAh g−1 (413.5 mAh g−1 Fe) still retains even at a high rate up to 5C) and excellent cyclic stability (with retention of as high as 75.9% of its highest capacity after 300 cycles at 1C). Meaningfully, our study proposes a sustainable and economical approach to produce advanced anodes for alkaline Ni-Fe secondary batteries, simultaneously providing an attractive and facile way to recycle spent LiFePO 4 materials in large scale. Graphical abstract Image 1 Highlights • LiFePO 4 /C/FeS composite is prepared from spent LiFePO 4 via a facile approach. • LiFePO 4 /C/FeS(40%) anode shows satisfied high-rate performance and cycle stability. • A new type of Ni-Fe battery with LiFePO 4 /C/FeS anode is successfully developed. • The electrochemical reaction process of LiFePO 4 /C/FeS anode has been studied. [ABSTRACT FROM AUTHOR]