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In this letter, two novel broadband circularly polarized slot-microstrip antennas (SMPA) with circular and square structures are elaborated. The circular SMPA is composed of four crown patches as parasitic elements, four crown slots etched on a circular ground plane, and a circular loop sequential phase feeding structure. However, the square SMPA consists of four parasitic rectangular patches, four square slots with cut corners, and a square-loop feeding structure. In the circular SMPA, the parasitic crown patches and crown slots are used to excite multiple circularly polarized (CP) resonant modes, which are fed by a circular loop sequential phase feeding structure through capacitive coupling. Combined with these CP modes, the CP bandwidth of the presented antenna could be improved. Eventually, the proposed circular SMPA has a broad 3-dB axial ratio bandwidth (ARBW) of 20.6% (5.206.40, 5.8 GHz) and a wide 10-dB impedance bandwidth (IBW) of 25.8% (4.926.38, 5.65 GHz), which could occupy the WLAN (5.7255.85 GHz), ITS (5.8 GHz), and WIFI (5.85-5.925 GHz) bands.

In this paper, systematic characterization of the dual probe, which is designed for the near field simultaneous measurement of both electric and magnetic field, is investigated with a microstrip line as the device under test (DUT). The characterization includes frequency response, transmission performance, symmetry, reflection, the intrusion of probe to the DUT, isolation of electric and magnetic field responses, field profile and spatial resolution, and differential electric field suppression. The dual probes with different design are adopted to demonstrate the systematic characterization.

Electromagnetic patterns in near field scanning usually give important information about the source inside an device under test. In this paper, we develop a postprocessing technique, including standard-deviation-based method, principal component analysis, and K -means method, so that the electromagnetic patterns in near field scanning can be extracted fast and grouped automatically and efficiently. The postprocessing techniques are applied to experimental near-field scanning of ICs, such as a microcontroller unit (MCU) and a field programmable gate array (FPGA). The grouping on the electromagnetic patterns of the MCU is in good agreement with the published grouping result, and the grouping on the electromagnetic patterns of the FPGA can find out the additional cluster responsible for additional circuit.

To measure the magnetic near field with high common-mode noise rejection, a probe with the differential and symmetrical structure forming a detection loop is developed. Such measurement is performed by using a two-port vector network analyzer (VNA) and validated by using a microstrip line as a device under test (DUT). In comparison to the measurement with traditional single-output magnetic near field probe, the electric field suppression of the proposed measurement can be improved by at least 10 dB in the frequency range of $3\sim 11$ GHz, while the other characteristics remain unchanged.

In this paper, the radiated emission of a microcontroller integrated circuit is investigated by rotating the test board in a transverse electromagnetic (TEM) cell measurement. The dependence of the radiated emission on the angle of rotation is derived on the basis of the coupling between a microstrip line and the TEM cell, and then validated by the multiple-orientation TEM cell measurements in a quantitative accuracy of fitting. With the validated dependence, the radiated emissions contributed by electric and magnetic coupling are extracted. The extracted emissions are found in agreement with the measurement result by near-field scanning experiments.

With the trend of miniature, high-integrated assembly modules are common in modern industry. The measurement of the flowing current and voltage on a trace is basic for diagnosis and monitoring of these modules. The traditional contact detection method is not practical especially in conditions of high power and small space. In this paper, we demonstrate a novel method for collocated and simultaneous measurements of radio frequency current and voltage on a trace in a noncontact and movable manner. The measurements are achieved by using a compact probe with both voltage and current detectors, as well as an algorithm based on the transfer functions quantifying the capacitive and inductive couplings between the detectors and the tested trace. The proposed method is verified and applied for continuous power measurements, collocated and simultaneous measurements of transient voltage and current pulses and the dynamic voltage and current of a switching device.

A near-field scanning is usually time-consuming to map the electromagnetic field along the surface of a device. In this communication, a dual probe is proposed with a U-shaped loop to sense radio frequency (RF) magnetic and electric fields simultaneously, so that the one-time scanning by the dual probe can replace the two-time scanning by single-detector probes. Different from the traditional near-field scanning by using a single-detector probe and spectrum analyzer, the proposed scanning can be achieved by the two-output probe and a two-port vector network analyzer connecting to the probe. The efficient near-field scanning measurements of the electric and magnetic field on a conductor-backed coplanar waveguide transmission line and an RF power divider by using the dual probe are in agreement with those by using two single-detector probes.

Hexagonal ground-shielding through silicon vias (TSVs) in 3D ICs are explored based on measurement and simulation. The measured S-parameters of the TSV-bundle part are successfully extracted by de-embedding technique. The results math well with simulations up to 20GHz. The proposed TSV bundle has a good performance of return and insertion loss. For the hexagonal ground TSV shield system, the crosstalk analysis of neighbor signals in the TSV shield system is made based on the measurements and simulations. The electronic and magnetic field plots show a good capacitive and inductive coupling isolation for the victim signal TSV with shielding ground TSVs. Compared to those coupled-TSVs systems without ground guide, the ground-shielding TSV as well as coaxial TSV has higher noise over the range of frequencies.

This paper presents a noncontact radio frequency voltage sensing of a printed trace by using a capacitive-coupled probe. The noncontact voltage sensing is demonstrated by using an open-end coaxial probe, and achieved through the transfer factor from the printed trace to the probe and a reconstruction algorithm. To validate the voltage sensing, known periodic, and pulse voltages are injected into the printed trace and compared with the reconstructed waveforms. Our results demonstrate that the voltage sensing method can be used for measurement of a random waveform with period even down to 1 ns and single pulse with rise time down to 2 ns. In consideration of the flexible relocation of the probe, the voltage sensing accuracy caused by spatial errors is also investigated.

Degradation characteristics and mechanisms of AlGaN/GaN high electron mobility transistors (HEMTs) were investigated under swift heavy-ion irradiation. AlGaN/GaN HEMTs were exposed to 800 MeV Bi ions with fluence up to 5.28 × 10 10 ions/cm 2 . Post-irradiation measurement shows that the saturation drain current reduced by 15%, the maximum transconductance decreased by more than 27%, and both the positive and negative gate characteristics degraded dramatically. By the off-state examination using the Photo Emission Microscopy (PEM), electroluminescence hot spots were found in the gate areas, which indicates new leakage passages produced by heavy-ion bombardment. Micro cross sections were prepared at hot spot areas by dual-beam focused ion beam (FIB) and examined using transmission electron microscope (TEM). The presence of latent tracks throughout the whole hetero-junction area was confirmed. Latent tracks, which related to the high density ionizing energy-loss, play a role of new leakage paths and account for the increment of gate leakage. Moreover, nonionizing energy-loss induced defects decrease the charge density in the two-dimensional electron gas (2DEG) and reduce the carrier mobility, leading to the degradation of device output performances.

This paper presents the total ionizing dose (TID) radiation performances of core and input/output (I/O) MOSFETs from 130 nm partially-depleted silicon-on-insulator (PDSOI). Both the core NMOS and PMOS are totally hardened to 1.5 Mrad(Si), while the I/O devices are still sensitive to TID effect. The worst performance degradation is observed in I/O PMOS which is manifested as significant front gate threshold voltage shift and transconductance decrease. Contrary to PMOS, front gate transconductance overshoot is observed in short channel I/O NMOS after irradiation. A radiation induced localized damage model is proposed to explain this anomalous phenomenon. According to this model, the increments of transconductance depend on the extension distance and trapped charge density of the localized damage region in gate oxide. More trapped charge lead to more transconductance increase. These conclusions are also verified by the TCAD simulations. Furthermore, the model presents a way to extract the trapped charge density in the localized damage region.

In this paper, we study the orientation effect of magnetic and electric field-to-line coupling (FtLC) between a microstrip line and a TEM cell by using a square-shaped transmission line pulse as an interference source. With the detections at enough orientations, the electric and magnetic FtLCs can be extracted with high accuracy. It is found that in the TEM cell, the ratio of electric to maximum magnetic FtLC is dominated by the characteristic impedance of the studied microstrip line due to the determined value of width-to-distance. For a certain ratio of electric to maximum magnetic FtLC, there is a singular angle at which the microstrip line gives no response for any electromagnetic interference excitation. Meanwhile, at the supplementary angle, the response of the microstrip line shows no dependence on the termination load.

In this paper, the electrical properties and low-frequency noise for bipolar junction transistors irradiated by 170 keV proton are examined. The result indicates that for the sample under proton irradiation with fluence 1.25 × 1014 p/cm2, base current IB in low bias range (VBE < 0.7 V) increases due to superimposition of radiation-induced recombination current, while the gain decreases significantly. Meanwhile, the low-frequency noise increases in the proton-irradiated sample. By analysis of evolution of parameters extracted from low-frequency noise power spectra, it is demonstrated that radiation-induced noise is mainly originated from carrier fluctuation modulated by generation–recombination centers (G–R centers) located at the interface of Si/SiO2, which are introduced by proton-radiation-induced defects. It is also confirmed that the electrical properties and noise behavior of irradiated sample are mostly affected by the carrier recombination process caused by G–R centers at the interface of S...

To provide a guideline for converter design and fault protection, the failure mechanism and reliability of silicon carbide (SiC) power MOSFETs needs to be further investigated. In this paper, the failure mechanism during short-circuit (SC) of commercial 1.2-KV/19-A SiC power MOSFETs was investigated. After the SC tests, the I ds of the device decreased significantly. Moreover, it was found that the V th and I gs increased obviously. The results demonstrated that negative charges were captured by the gate oxide and accumulated during the SC tests, which is eventually causes degradation of the gate oxide. The results of this study may be useful in the design and application of SiC power MOSFETs.

Lithium sulfur (Li-S) batteries are very promising electrochemical storage system due to their high gravimetric energy density and low cost. Enormous efforts have been put on Li-S battery to achieve its commercialization. The function of electrolyte is a key issue in achieving the high performance of Li-S system, and several additives have been tried. But very few works have been working on the electrolyte optimization method with the consideration of over-all performance, including cycling stability, rate capability, especially self-discharge prevention ability, and the consideration of loading condition. In this work, we focus on the incorporation of room temperature ionic liquid (IL) as co-solvent, and the effect of IL in mitigating the polysulfide dissolution via systematical mechanism study of self-discharge phenomena. Moreover, the optimization of IL incorporation ratio is discussed for the sake of the better over-all electrochemical performance of Li-S cell by considering cycling stability, rate performance and self-discharge prevention ability, which is found to vary with loading condition. The improved understanding of the effect of IL on battery performance will help the development of electrolyte for Li-S batteries.

Displacement damage induced degradations in four-junction solar cells are investigated by electron irradiation and TCAD simulation. It shows that In0.3Ga0.7As cell is the key sub cell to affect the radiation tolerance of four-junction solar cell. Although irradiation will introduce relatively uniform displacement damage in each sub cell of four-junction solar cell, the In0.3Ga0.7As cell show the most significant degradation under the same radiation damage conditions. The radiation harness of the four-junction solar cell can be promoted by increase the short circuit current of In0.3Ga0.7As cell before irradiation, which is verified by the TCAD simulations. The relationship between electrical characteristics degradations and the displacement damage dose is established for four-junction solar cells. Then, the equivalent displacement damage dose method has been used to predict the on-orbit degradation of four-junction solar cells. The degradations of the four-junction solar cells on typical geosynchronous earth orbit are calculated by combining Monte Carlo simulations and ground irradiation test data.

Field Programmable Gate Array (FPGA) system is widely used in deep learning application and cloud system for acceleration. Quality and reliability of IP block is essential to the successful development of today's complex hardware acceleration design. In this paper, we discuss the important issues of quality and reliability of digital soft IP, and propose a qualification measurement system that can evaluate IP quality. The metric system consists of eight categories to characterize IP quality. Based on this indicator system, we propose an IP qualification frameworks. As a case study, the proposed framework has been used to qualify three open source IP cores. The experimental results show that the proposed metric system and qualification framework can not only quantify the quality of IP, but also speed up the certification process and improve the accuracy of the certification results.

As we known, the measurement of junction-to-case thermal resistance (R th -JC) of semiconductor power devices is very important. In this paper, an approach of transient dual interface method (TDIM) with gate-source voltage (Vg s ) as the temperature sensitive electrical parameters (TSEP) was investigated for the measurement of R th -JC of packaged SiC MOSFET. The measured R th -JC value of packaged SiC MOSFET is in the range of 1.61 K/W to 1.76 K/W, and compared with the typical value of device specification, the maximum error is 5.29 %. The results show that the thermal resistance measurement of packaged SiC MOSFET by TDIM with Vg s as the TSEP is feasible, and it is of good accuracy and reproducibility.

In this paper, a simulation tool named the neutron-induced single event effect predictive platform (NSEEP2) is proposed to reveal the mechanism of atmospheric neutron-induced single event effect (SEE) in an electronic device, based on heavy-ion data and Monte-Carlo neutron transport simulation. The detailed metallization architecture and sensitive volume topology of a nanometric static random access memory (SRAM) device can be considered to calculate the real-time soft error rate (RTSER) in the applied environment accurately. The validity of this tool is verified by real-time experimental results. In addition, based on the NSEEP2, RTSERs of 90 nm–32 nm silicon on insulator (SOI) and bulk SRAM device under various ambient conditions are predicted and analyzed to evaluate the neutron SEE sensitivity and reveal the underlying mechanism. It is found that as the feature size shrinks, the change trends of neutron SEE sensitivity of bulk and SOI technologies are opposite, which can be attributed to the different MBU performances. The RTSER of bulk technology is always 2.8–64 times higher than that of SOI technology, depending on the technology node, solar activity, and flight height.

The instabilities of indium–zinc oxide thin film transistors under bias and/or illumination stress are studied in this paper. Firstly, illumination experiments are performed, which indicates the variations of current–voltage characteristics and electrical parameters (such as threshold voltage and sub-threshold swing) are dominated by the stress-induced ionized oxygen vacancies and acceptor-like states. The dependence of degradation on light wavelength is also investigated. More negative shift of threshold voltage and greater sub-threshold swing are observed with the decrease of light wavelength. Subsequently, a negative bias illumination stress experiment is carried out. The degradation of the device is aggravated due to the decrease of recombination effects between ionized oxygen vacancies and free carriers. Moreover, the contributions of ionized oxygen vacancies and acceptor-like states are separated by using the mid-gap method. In addition, ionized oxygen vacancies are partially recombined at room temperature and fully recombined at high temperature. Finally, low-frequency noise is measured before and after negative bias illumination stress. Experimental results show few variations of the oxide trapped charges are generated during stress, which is consistent with the proposed mechanism.

Based on a method combined artificial neural network (ANN) with particle swarm optimization (PSO) algorithm, the thermo-mechanical fatigue reliability of plastic ball grid array (PBGA) solder joints was studied. The simulation experiments of accelerated thermal cycling test were performed by ANSYS software. Based on orthogonal array experiments, a back-propagation artificial neural network (BPNN) was used to establish the nonlinear multivariate relationship between thermo-mechanical fatigue reliability and control factors. Then, PSO was applied to obtaining the optimal levels of control factors by using the output of BPNN as the affinity measure. The results show that the control factors, such as print circuit board (PCB) size, PCB thickness, substrate size, substrate thickness, PCB coefficient of thermal expansion (CTE), substrate CTE, silicon die CTE, and solder joint CTE, have a great influence on thermo-mechanical fatigue reliability of PBGA solder joints. The ratio of signal to noise of ANN-PSO method is 51.77 dB and its error is 33.3% less than that of Taguchi method. Moreover, the running time of ANN-PSO method is only 2% of that of the BPNN. These conclusions are verified by the confirmative experiments.

Hardware Trojan embedded by adversaries has emerged as a serious security threat. Until now, there is no a universal method for effective and accurate detection. Since traditional analysis approaches sometime seem helpless when the Trojan area is extremely tiny, this paper will focus on the novel detection method based on frequency spectrum analysis. Meanwhile, a failure physics model is presented and depicted in detail. A digital CORDIC IP core is adopted as a golden circuit, while a counter is utilized as a Trojan circuit. The automatic test platform is set up with Xilinx FPGA, LabVIEW software, and high precision oscilloscope. The power trace of the core power supply in FPGA is monitored and saved for frequency spectrum analysis. Experimental results in time domain and frequency domain both accord with those of theoretical analysis, which verifies that the proposed failure physics model is accurate. In addition, due to immunity to vast measurement noise, the novel method processing in frequency domain is superior to the traditional method conducting in time domain. It can easily achieve about 0.1% Trojan detection sensitivity, which indicates that the novel detection method is effective.

This paper proposed a two-dimensional thermal impedance model for amorphous silicon thin film transistors (a-Si:H TFTs) from a system of coupled energy equations, heat flowing equations and boundary conditions. By using of this model, the channel temperature distribution and thus the maximum channel temperature can be calculated. This model can be applied to describe the thermal behavior and thermal reliability of a-Si:H TFTS in the design phase.

Electromagnetic interference effects in the bipolar voltage comparator was investigated in this paper. By using of bulk current injection (BCI), the coupling current stimulated by high power electromagnetic pulse was simulated. The experimental results shown that the aberrations such as pulse deriving and pulse width altering will come into being in the output waveforms of LM139 after current injection respectively. Furthermore, the coupling effect of pulse deriving and pulse width broadening were observed simultaneously in the higher level current injections.

Malicious modification of integrated circuits referred to as Hardware Trojan fabricated in untrusted foundries pose a growing concern on reliable and security application. In order to ensure trusted in-filed operation of integrated circuits, many techniques are developed to authenticate Hardware Trojan often called trojan detection. Among these techniques side-channel signals analysis is a widely researched method to detect Hardware Trojan but suffer from sensitivity decreasing caused by increasing process variation effects. In this paper, we propose a non-invasive Hardware Trojan detection method which is immune to process variation effects. The method exploits the intrinsic relationship between transient current (I ddt ) and quiescent current (I ddq ) and I DDT of different test vectors that can eliminate the effects of process variation. The proposed method is verified by Hspice simulation carried on ISCAS 85 benchmark circuit. The 100 times simulation results with 130nm CMOS process using Monte Carlo method show that the suggested methods are capable of detecting the Hardware Trojan whose equivalent area is as small as 10"4 of the total size of the circuit in the presence of ±7% parameter(threshold voltage) variations.

Modern science is pushing Integrated circuits (IC) to higher level of integration, internal clock frequency and translation rates. In this context, the electromagnetic compatibility (EMC) of IC has gained more and more significance in the design stage, as well as the qualification. In this paper, the near field characterization is performed on a newly-built scanning system, in which a spectrum analyzer is used to detect the electromagnetic signal of the device under test. The scanning and detecting for the electromagnetic interference (EMI) is verified by a testing on the magnetic field above a microstrip. And then we apply the method to near field characterization of EMI for a microcontroller (C8051F120). The microcontroller is set to work at two different frequencies, 24.5MHz and 98MHz. The harmonic frequency is found in the range up to 500MHz. It is found that the excitation of phase lock loop module is significant for the whole electromagnetic radiation. The pins with higher EMI radiation are also identified in this paper.

Malicious modification of integrated circuits, namely Hardware Trojan, has emerged as a major security threat. Since it is extremely difficult to detect the presence of such small Trojan circuits using only logic test or side-channel analysis, this paper presents a novel test method combining logic test and side-channel test together. An 18-bit CORDIC IP core is adopted as a golden circuit, while a 2-bit counter is applied as a Trojan circuit. The automatic test platform is set up with Xilinx FPGA, LabVIEW software, and high precision oscilloscope. Meanwhile, the power traces of power supplies V ccint or V ccaux in FPGA are both monitored to enhance the detection sensitivity. The relevant test flow chart is also depicted in detail. Experimental results demonstrate that the novel test method can easily achieve about 0.1% Trojan detection sensitivity when principal component analysis approach is adopted as the data processing algorithm.

Total ionizing dose (TID) radiation effects in the bipolar voltage comparator with different biases and dose rates were investigated in this paper. The experimental results show that offset voltages shift after irradiation. Dominated by the current gain degradation of differential PNP transistors, the shifts of offset voltage and output characteristics were significantly affected by biases at high dose rate. Dominated by the current gain degradation of NPN transistors, the shifts of offset voltage and output characteristics were similar in all biases at low dose rate.

Firstly, the storage failure mode and failure mechanism study of the klystron was carried out, the main failure modes of klystron in storage were summarized, and the failure mechanism and failure reasons of the main failure mode were analyzed. The results of the study showed that the vacuum degree decline is the main reason for the failure in long-term storage of klystron. The vacuum degree decline of tube is due to the residual gas of in seal manufacturing process or the deflation and shell leakage of the tube during the period of storage. Secondly, the generation process of residual gas was studied. At last, a failure sample of long-term storage klystron was analyzed; results showed that the failure mechanism was due to a large number of evaporation the cathode emission material which induced the serious degeneration of cathode, then the cathode emission current reduced and the out power declined. The reason of cathode degradation was vacuum degree decline in long-term storage process, ions back to the cathode surface that caused the huge evaporation of cathode emitting material.

Experimental evidences are presented showing the variety of supply voltage dependence of single event upset (SEU) sensitivity in diverse SRAM devices. Devices under test (DUTs) from Alliance Memory, ISSI and IDT companies with different technologies were irradiated by several kinds of heavy ions at Heavy ion Research Facility in Lanzhou (HIRFL) cyclotrons. For the Alliance 256 kb SRAM device, SEU cross section increases by more than one order of magnitude as supply voltage decreases from 5.0 V to 3.0 V. SEU data of Alliance 64 kb SRAM also exhibits significant supply voltage dependence. The reduction of critical charge is the predominant factor worsening the device performance. While for the Alliance 8 Mb, ISSI 2 Mb and IDT 256 kb SRAM devices, no obvious trend was observed, which is attributed to the negligible net contribution of competing mechanisms. Those results suggest that the worst-case supply voltage for evaluation of SEU sensitivity depends on the test devices.

We have submitted the AlGaN/GaN High electron mobility transistors (HEMTs) to the high temperature reverse bias(HTRB) stress to assess their reliability for high voltage operations. The effects of HTRB stress as a function of the V DG and stress time on the DC parameters and trapping effects were investigated. The study was based on combined DC and pulsed characterization, transient measurement. It provides the following information: 1) the exposure to HTRB may result in a permanent degradation in on-state current, the transconductance, and a slightly positive shift of threshold voltage; 2) the high temperature (T A =175°C) step reverse bias (V DG stepped from 20V to 80V) stress tests revealed that the gate leakage current I GS increased abruptly after 50V stress voltage V DG ; 3) interestingly, the long term high temperature moderate reverse bias(V DG 40V) stress resulted in some positive effects such as the decrease of gate leakage current, improved gate lag characteristics and the decrease of current collapse in pulsed measurement during the whole test; 4) the reverse-bias voltage is the key factor but for reliability assessment of AlGaN/GaN HEMTs for high voltage application based on HTRB stress; 5) The degradation mechanism of the gate leakage current under relatively high voltage HTRB test has been ascribed to the degradation metal and semiconductor interface; 6) the improved I-V characteristic under moderately voltage HTRB test has been attributed to the reduction of lateral tunneling current.

This paper presents an equivalent circuit approach to evaluate the effect of near-zone electromagnetic interference on the shielding effectiveness (SE) of an apertured rectangular enclosure. The approach is an extension of Robinson's equivalent circuit formulation. The extension in this paper is carried out by using an electric dipole to represent the external interference and applying the electric field at the aperture caused by the dipole to replace Robinson's incident plane wave. The SE correlates to the dimensions of the enclosure and the aperture. The distance from the interference to the enclosure and the observed position within the enclosure are significant parameters on the SE evaluation. The shapes of the aperture also affect the SE. This equivalent circuit approach based on the available analytical formulation provides a fast means of investigating the effect of design parameters on the SE of an apertured enclosure for near-zone interference and can be used for designers of shielded enclosures.

This paper presents a novel optimization design method for the closed loop control of the sense mode of a MEMS gyroscope, which aims at improving the performances and reliability of the control system.

Along with the infrared technical rapid development, infrared radiation (IR) thermal imaging technology is widely applied in device and circuit reliability research. For device and circuit reliability study, IR thermal imaging technology is best for getting the peak temperature and temperature distribution. With the peak temperature and temperature distribution, the thermal information of the devices were evaluated and optimized to meet the design requirement. Secondly, IR thermal imaging technology is used to position hotspot for failures analysis, example for especially increases in elevated leakage currents. However, IR thermal imaging technology can provide evidence of excessive temperature rise due to power dissipation. It can identify root-cause of failures at temperatures below expectations.

Space traveling wave tube (TWT) is one kind of microwave vacuum tube for communication, which must have high reliability, high power. The life of the space TWT is requested for a long lifetime of 10–15 years. In order to shorten the testing process, accelerated aging tests are performed at higher than normal operating temperature and currents of cathode. But in the process of the actual test, the cathode degradation is very slow, the test time is too long for all samples failing to get the lifetime data. In order to obtain the lifetime of the long life tube in a short time, it is necessary to investigate a new method which can evaluate the long lifetime through short-term working data. This paper introduced how to solve the zero-failure test data with small samples. With no failure data in data processing of life test, parameter degradation extrapolation method is used to obtain the failure life time. All the expected life of the sample was estimated of each test samples by least-square method for linear fitting and the goodness of fit and the significance testing was done.

The total-dose-induced edge effect in SOI NMOS transistors with different layouts is presented. Experimental results show that the edge effect is very sensitive to their layouts. Among the transistors hardened by design, the H-gate and ringed-source transistors do not behave as expected. At high radiation doses, the edge leakage currents appear for both transistors. Compared to the unhardened two-edged transistor, their total-dose-induced edge leakage paths and the role of layouts on edge effect are discussed.

Total Dose ionizing radiation response of substrate PNP transistors have been investigated as functions of biases and dose rates. The experiment result shown that emitter-base junction bias dominates dose rate effects in the SPNP transistors. By considering of radiation induced interface traps and oxide trapped positive charges, the degradation mechanisms have been discussed based on space charge model. In addition, the worst case biases in the SPNP transistor with different dose rates are also discussed in this paper.

This paper proposed a physical model for reverse subthreshold currents in the amorphous silicon thin film transistors. Firstly, an approximation for the band bending in the back interface as a function of gate-source voltage is derived. By considering of deep states, a current model based on electron conduction in the back channel is then developed. Finally, the proposed model was verified using the experimental data.

The failure rate for NMOS devices is modelled by sum-of-failure-rate, i.e., the one for HCI mechanism and the one for TDDB failure mechanism. The least squares method is used to estimate the unknown parameters in HCI failure rate model and TDDB failure rate model, respectively. The hypothesis tests show that the regression model for HCI (TDDB) has good fitness and high significance. These results are verified by a numerical example.

A prognostic circuit for electromigration failure of integrated circuit was proposed, and it was simulated on the base of the SMIC 0.18 um mixed-signal CMOS process model. The prognostic circuit is composed of stress and detection module, two-stage comparator, offset voltage cancellation module, non-overlapping clock generation module, and output module. When the increase amount of resistance for interconnect line exceeds a preset value due to electromigration, the output of the prognostic circuit designed to fail faster will jump from low voltage to high voltage. It indicates the impending failure of hosted circuit because of that the prognostic circuit experiences the same manufacturing process and operational environment as the hosted circuit. The research results are useful for the prediction of performance degradation and failure of integrated circuit.

This paper investigates the total dose effects of substrate PNP transistors through experiments. By considering of oxide trapped positive charges and interface traps, the radiation induced excess base current in the irradiated SPNP is simulated. The simulation results showed similar trends with the experimental results, thus the mechanisms of total dose effects in the SPNP transistors are verified.

Traveling wave tube (TWT) is a type of microwave vacuum electronic component. TWT often works under harsh mechanical environment stress, such as vibration, shock. The stress leads to the open circuit of filament in heater, which results in the change of inner structure and electric performances, even failure. This paper introduced a failure case of TWT in use. Failure mode and failure mechanism of filament in heater of a typical TWT was analyzed in this paper.

Ionization radiation causes ESD protection structure of integrated circuit degradation. A new method using Transmission Line Pulse (TLP) test is introduced in this article; this method gives more detailed information of the ESD protection structure's degradation. Turn-on voltage, hold voltage, turn-on resistance of two type ESD protection structures are measured before and after TID radiation test, results are discussed.

An investigation of thermal effects in a high power 3-5μm solid state laser pumped with different pump beam transverse profiles is carried out by COMSOL software based on the finite element method, and the temperature of the crystal center where the Super-Gaussian distributed light projected area is 81.8°C, and is bigger than that of Gaussian pump light mode and top plane pump light mode.

The electromagnetic interference effects in the μA741 operational amplifier circuit were investigated in this paper. Through the using of pulse injection, the output characteristics of μA741 were simulated by considering of EMI effects. Through sensitivity and smoke analysis, the simulation results shown that the differential input stage and the intermediate amplifying stage are the most sensitive and vulnerable function model in the μA741 circuits to EMI effects.