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During heavy-ion experiments, the single-event gate rupture (SEGR) effects can still be observed in the vertical double-diffused power MOSFET (VDMOS) with radiation-hardened cells. Fault analysis demonstrates that the hot spots locate at the termination of the VDMOS. Then, several mitigation solutions for termination structure are discussed comprehensively by means of TCAD simulations. Finally, a combined hardness method with horizontally extending P+ region and adding floating N+ region is proposed. It is effective to reduce the electric field of gate oxide to below the calculated critical field, without additional masks and process steps. [ABSTRACT FROM AUTHOR]

In the harsh space environment, the phase-locked loop (PLL) circuit is vulnerable to radiation effects, which will lead to performance degradation or even function interrupts. In this article, a rad-hard low-noise PLL is designed with low power and area overhead and verified in a 130-nm silicon-on-insulator process. Heavy ion test demonstrates that the proposed PLL is immune to the single-event effect up to 83.7 MeV·cm2/mg. Furthermore, its single-event sensitivity is characterized and compared with an unhardened PLL by the pulsed laser test. Finally, the gamma-ray radiation experiment confirms that it can provide >300 krad(Si) total ionizing dose assurance. [ABSTRACT FROM AUTHOR]

The sensitivity of total-ionizing-dose (TID) response on a single-event hardened phase-locked loop (PLL) fabricated in a 130-nm silicon-on-insulator process is investigated. Based on the study of device parameter degradation under radiation exposure, the changes of dc and RF performance of the PLL have been presented. TID experiments on the PLL show that the power-down current increases by 1.5 times, and the tuning range drops by 11.5%. At 600 MHz and up to 500 krad(Si), the integrated phase noise increases by 29.2%, and the reference spur increases by 3.4 dB. Finally, the mechanism underlying impact of TID on the phase noise and reference spur has been discussed comprehensively, which combined measured observations with circuit modeling and simulations. [ABSTRACT FROM AUTHOR]

A radiation-hardened low-jitter phase-locked loop (PLL) with a low-mismatch charge pump and a robust voltage-controlled oscillator is designed in a 130 nm PD-SOI process. In order to evaluate the overall response to single-event effects, the accumulated phase jitter has been put forward, which can exclude the inherent noise floor and accumulate all the radiation-induced noise. Then the single-event sensitivity of the proposed PLL is comprehensively analyzed by heavy ion and pulsed laser tests. [ABSTRACT FROM PUBLISHER]

In this paper, a radiation-tolerant phase-locked loop (PLL) is designed and fabricated with 130 nm PD-SOI technology. A current-based charge pump is hardened using a current compensation technique in combination with the differential charge cancellation (DCC) layout of the complementary switches. Besides, the stacked SOI transistors are employed to mitigate single-event effects of the voltage-controlled oscillator. The experimental results show that the proposed PLL has no significant jitter variations under heavy-ion experiments, compared with TMR-hardened PLL. Besides, pulsed-laser testing comprehensively characterizes the single-event transients of the PLL and demonstrates its radiation tolerant performance. [ABSTRACT FROM PUBLISHER]

Existing studies demonstrate that the identity formation of internationally adopted children and the adjustments of adoptive families reside in the processes of cross-cultural and intercultural communication. However, there have been few studies on international adoption from the perspectives of intercultural and cross-cultural communication. Following a previous qualitative study on the experiences of adult international adoptees, this project employs a quantitative method to examine the ongoing (before, during, and after adoption) cross-cultural adaptation and identity formation of international adoptees from the perspectives of adoptive parents. The findings of the study have identified the key issues involved in the cross-cultural adaptation process and discussed experiences of adoptive families for dealing with those issues. [ABSTRACT FROM PUBLISHER]

A surface-potential-based model is developed for the symmetric long-channel junctionless double-gate MOSFET. The relationships between surface potential and gate voltage are derived from some effective approximations to Poisson's equation for deep depletion, partial depletion, and accumulation conditions. Then, the Pao–Sah integral is carried out to obtain the drain current. It is shown that the model is in good agreement with numerical simulations from subthreshold to saturation region. Finally, we discuss the strengths and limitations (i.e., threshold voltage shifts) of the JLFET, which has been recently proposed as a promising candidate for the JFET. [ABSTRACT FROM AUTHOR]

Explores teacher-student relationships in college education. Examination of organizational cultures in the classroom; Concepts on instructors' concern for students; Propositions on teaching as a mode of friendship.

Presents a study which examined ethnic identities of Chinese American children living in the Chicago and San Francisco Bay Areas. Method; Results and discussion.

In recent years, micro-nano device characteristics like ferroelectrics and resistive switching are being used to build important security primitives such as Physical Unclonable Function (PUF). The micro-nano device-based hardware security primitives, although with higher security, energy efficiency, and integration density, suffer from serious reliability issues caused by process scaling. To mitigate this issue, this paper introduces a reconfigurable weak PUF based on spin-transfer torque magnetoresistive random-access memory (STT-MRAM), which adopts the crossing switches implemented with simple demultiplexes (DEMUXs) to improve the flexibility and reliability. Moreover, two algorithms, neighboring bit lines and top- $n$ n , are proposed to enlarge the gap between two parallel reading currents, thus further enhancing the reliability of PUF responses. Experimental results demonstrate that the proposed PUF scheme achieves good uniqueness (50.64 percent), uniformity (50.02 percent), and bit-aliasing ($\approx$ ≈ 49.80%). Particularly, the proposed method significantly improves the PUF reliability, achieving low bit error rate (BER $\leq$ ≤ 2.13%) within the range of -20 $^\circ$ ∘ C to 90 $^\circ$ ∘ C. [ABSTRACT FROM AUTHOR]

• A compact LDMOS-DDSCR for dual-direction HV ESD protection is proposed to achieve low trigger voltage and high failure current. • The failure current of new proposed LDMOS-DDSCR raises from 2.00A to 4.02A. • The new proposed LDMOS-DDSCR shows good temperature reliability. The LDMOS-based silicon controlled rectifier (SCR) is commonly used in high voltage (HV) electrostatic discharge (ESD) protection due to its great current handling capability per area and HV protection ability. In this paper, an improved LDMOS-based dual direction SCR (LDMOS-DDSCR) device is designed by replacing floating N+ region with electrically-connected P+, N+ and P+ regions to enhance its ESD robustness, which is verified in a 0.5-μm (1p2m) 18 V HV CDMOS process. The internal mechanism of the proposed device is analyzed using two-dimension (2D) TCAD simulations, and the ESD performance is characterized by means of transmission line pulse (TLP) and very-fast TLP (VFTLP) measurements. Compared with the conventional LDMOS-DDSCR, the failure current of the compact LDMOS-DDSCR raises from 2.00 A to 4.02 A (increased by 101%), and the trigger voltage reduces from 44.28 V to 39.76 V, without sacrificing layout area. Furthermore, the TLP I-V curves of the proposed LDMOS-DDSCR are measured at different temperatures ranging from 25 °C to 125 °C, which proves its reliability and show potential use in the applications of high voltage integrated circuits. [ABSTRACT FROM AUTHOR]

Reflecting on Shing-Ling Chen's experience of being a Leukemia child's mother encountering others' seemingly hurtful support of her misery, the authors address the ethics of having fun activities as fundraisers for victims of traumatic events. The authors question the adequacy of hosting entertaining activities to fundraise for victims of Asian Tsunami, or patients of amyotrophic lateral sclerosis (ALS; that is, the ALS ice-bucket challenge) and cancers (e.g., polar plunge), and so on. The social dynamics and communication processes involved in these events are analyzed. [ABSTRACT FROM AUTHOR]

In application scenarios such as astronautics, high-altitude aircraft, medical radiography, high-energy physics, and nuclear power plants, the irradiation resistance of electronic components is one of the basic requirements for their reliability. HfO 2 -based ferroelectric films have the advantages of high CMOS process compatibility, good miniaturizability, low operating voltage, and excellent irradiation resistance, which are the core materials for the new generation of irradiation resistance ferroelectric memories. In this paper, two kinds of metal-electrode ferroelectric capacitors, W/Hf 0.5 Zr 0.5 O 2 /W (WW) and Pt/Hf 0.5 Zr 0.5 O 2 /Pt (PP), have been prepared, and three gradient γ-irradiation experiments have been carried out on the two kinds of ferroelectric capacitors. The effect of metal electrodes on the irradiation resistance of Hf 0.5 Zr 0.5 O 2 ferroelectric thin films was carefully investigated by comparing and analyzing the statistical laws of polarization change and rectangularity change before and after irradiation of a large number of devices. The experimental results show that the WW devices have better irradiation resistance than PP devices, and we further explain the irradiation resistance mechanism by first-principle calculations and finite element analysis to verify the credibility of the experimental results. Finally, we conducted a comparative test of the fatigue and wake-up characteristics of the WW devices before and after irradiation, and the results show that the prepared W/Hf 0.5 Zr 0.5 O 2 /W devices can withstand very high total γ-dose radiation, reaching up to 13.86 Mrad(Si), and they are very suitable for the application of irradiation resistant electronics. [Display omitted] • The Hf 0.5 Zr 0.5 O 2 (HZO) thin films with outstanding ferroelectric properties were prepared. • The HZO ferroelectric thin films exhibited extremely high radiation tolerance (reaching up to 13.86 Mrad(Si)). • The effect of different metal electrodes on the irradiation resistance of HZO ferroelectric thin films was analyzed. [ABSTRACT FROM AUTHOR]

The reliability issues of integrated circuits are attracting more attention, especially in extreme environments like radiation and elevated temperature conditions. The impact of ionizing radiation and temperature effects on the electrostatic discharge (ESD) protection devices should not be negligible. In this paper, A low-voltage dual-direction silicon controlled rectifier (DDSCR) and a high-voltage DDSCR based on laterally diffused metal oxide semiconductor are chosen and fabricated in a 5 V/18 V Bipolar-CMOS-DMOS process. To study the combined effects of ESD and total-ionizing dose, transmission line pulse (TLP) measurements are conducted right after exposure to 60Co gamma-ray up to 200 krad(Si). Besides, the TLP tests are performed at different temperatures ranging from 300 to 400 K to show the impact of elevated temperature on ESD devices. In the meanwhile, the physical mechanisms of the synergistic effects are investigated by means of three-dimensional (3D) TCAD simulations. [ABSTRACT FROM AUTHOR]

To mitigate the total ionizing dose (TID) effects of the dual-direction silicon-controlled rectifier, based on laterally diffused metal–oxide–semiconductor (LDMOS-DDSCR), a common-centroid layout arrangement with multiple octagonal units is proposed and fabricated in an 18-V Bipolar-CMOS-DMOS process. The symmetrical characteristics of the bidirectional electrostatic discharge (ESD) protection are verified by transmission line pulse tests. Gamma-ray irradiation experiments demonstrate that the proposed device is tolerant of TID effects up to 100 krad(Si), whereas the traditional finger-type LDMOS-DDSCR loses its function at 50 krad(Si). Finally, the ESD performance is also characterized at high temperatures which confirms that the proposed device is an excellent candidate for space applications. [ABSTRACT FROM AUTHOR]

The reliability of power devices is attracting more and more attention, especially in the extreme radiation environment. The laterally diffused metal–oxide–semiconductor (LDMOS) has been widely used in high voltage integrated circuits. In this paper, the radiation effects of LDMOS transistors are extensively investigated through three-dimensional (3D) TCAD simulations, including Total-Ionizing Dose (TID), Single-Event Effect (SEE) and Transient Dose Rate Effect (TDRE). Firstly, the mechanism of TID effect on the LDMOS is revealed in consideration of temperature variations. Secondly, the single-event effect of the LDMOS is studied with different incident positions, linear energy transfer (LET) values, incident lengths, incident angles, bias conditions and temperatures. Besides, the combined effect of total-ionizing dose and single-event burnout is characterized. Finally, transient response of the LDMOS under transient γ radiation is also studied comprehensively. Therefore, it gives an insight into the physical mechanisms and response characteristics of complex radiation effects, which can provide guidance for radiation-hardened by design and application of the LDMOS devices. • The mechanism of TID effect on the LDMOS is revealed in consideration of temperature variations. • The most sensitive region to SEB of the LDMOS locates at the boundary between the channel and drift region. • Except for the off bias, the ON bias and subthreshold bias are also sensitive to SEB effect. • The physical mechanisms of the combined effects of SEB and TID are revealed. • Transient response of the LDMOS under transient gamma radiation is studied. [ABSTRACT FROM AUTHOR]

In this study, tantalum coatings are deposited by a plasma spraying method aiming at enhancing the biocompatibility of the titanium implant. Tantalum oxide coatings are gained through the thermal oxidation of tantalum coatings at different temperatures for photothermal therapy. The effect of thermal oxidation on the morphology, composition, and structure of tantalum coatings has been studied. The UV–VIS–NIR spectra results, cancer therapy effect in vitro, and photothermal conversion properties among the tantalum oxide coatings under varied thermal treatment conditions are compared comprehensively. It has been proven that the tantalum coating treated at 200 °C exhibits the most intense NIR adsorption, the highest photothermal conversion effect, and the most excellent photothermal ablation effect in vitro. The results reveal that incomplete oxidation at a low temperature leads to the formation of oxygen vacancies, which narrow the band gap; this promotes its photothermal conversion ability. [ABSTRACT FROM AUTHOR]

In this work, tantalum thin films were prepared on titanium substrates by an ion beam sputtering method. Tantalum thin films were irradiated by gamma-ray with different total dose levels. The effect of irradiation on the phase composition, microstructure, surface morphology, and chemical resistance were analyzed. Besides, in vitro cytocompatibility of tantalum films treated with different radiation doses were evaluated via 3T3-E1 cells. Experimental results showed that higher radiation dose resulted in reductions in crystalline nature, denser morphology, lower elastic modulus, less oxygen vacancies and better corrosion resistance. Additionally, 3T3-E1 cells adhered and spread well on the surface of tantalum film with irradiation exposure to 10 kGy. The dense surface morphology, less density of chemical defects and amorphous phase produced by the gamma-ray irradiation played a major role in the improvement of mechanical compatibility, electrochemical stability property along with the cytocompatibility of the tantalum films. • The effect of gamma-ray irradiation on the chemical resistance and cytocompatibility of tantalum film • Introduction of amorphous phase, denser morphology, and less oxygen vacancy at high total dose radiation • Improvement of electrochemical stability and cytocompatibility induced by gamma-ray irradiation [ABSTRACT FROM AUTHOR]

Responsitivity is an important figure of merit for photodetectors. Here we demonstrated a simple yet efficient way to enhance the responsitivity of methylammonium lead iodide (MAPbI 3)-based photodetectors by utilizing organic semiconductors (OSCs) to form MAPbI 3 /OSC bilayer structures. These bilayer photodetectors are fabricated with a facile and low-cost spin-coating method, yet the responsitivity can be more than one order of magnitude higher than that of pristine MAPbI 3 photodetectors. More importantly, the physics behind the enhancement of responsitivity was analyzed and revealed by inspecting the physical processes in terms of light absorption, exciton dissociation and charge transport. The results indicate that the responsitivity enhancement is mainly attributable to the more efficient exciton dissociation and hole transport processes in the bilayer photodetectors. Image 1 • In this work, we demonstated that the responsitivity of organic-inorganic hybrid lead halide perovskites (MAPbI 3) based photodetectors can be dramatically enhanced by forming MAPbI 3 /organic semiconductor (OSC) bilayer films, and the physics behind the responsitivity enhancement was clarified. • Considering that there are so many organic semiconductors with different optical and electrical properties, it may open up opportunities to explore different combinations of perovskites and organic semiconductors for achieving high-performance photodetectors, or finely tune the performance of photodetectors according to our needs. • This work thus can be important to the development of application of pervoskite/OSC bilayer photodectors. [ABSTRACT FROM AUTHOR]