Comprehensive Pyro‐Phototronic Effect Enhanced Ultraviolet Detector with ZnO/Ag Schottky Junction

As a coupling effect of pyroelectric and photoelectric effect, pyro‐phototronic effect has demonstrated an excellent tuning role for fast response p–n junction photodetectors (PDs). Here, a comprehensive pyro‐phototronic effect is utilized to design and fabricate a self‐powered and flexible ultraviolet PD based on the ZnO/Ag Schottky junction. By using the primary pyroelectric effect, the maximal transient photoresponsivity of the self‐powered PDs can reach up to 1.25 mA W^?1 for 325 nm illumination, which is improved by 1465% relative to that obtained from the steady‐state signal. The relative persistent secondary pyroelectric effect weakens the height of Schottky barrier, leading to a reduction of the steady‐state photocurrent with an increase in the power density. When the power density is large enough, the steady‐state photocurrent turns into a reverse direction. The corresponding tuning mechanisms of the comprehensive pyro‐phototronic effect on transient and steady‐state photocurrent are revealed based on the bandgap diagrams. The results may help us to further clarify the mechanism of the pyro‐phototronic effect on the photocurrent and also provide a potential way to optimize the performance of self‐powered PDs.     

Organic Junction Field‐Effect Transistor

The realization and performance of a novel organic field‐effect transistor—the organic junction field‐effect transistor (JFET)—is discussed. The transistors are based on the modulation of the thickness of a depletion layer in an organic pin junction with varying gate potential. Based on numerical modeling, suitable layer thicknesses and doping concentrations are identified. Experimentally, organic JFETs are realized and it is shown that the devices clearly exhibit amplification. Changes in the electrical characteristics due to a variation of the intrinsic and the p‐doped layer thickness are rationalized by the numerical model, giving further proof to the proposed operational mechanism.     

Nanostructured Si/Organic Heterojunction Solar Cells with High Open‐Circuit Voltage via Improving Junction Quality

Nanostructured silicon (Si) can provide improved light harvest efficiencies in organic‐Si heterojunction solar cells due to its low light reflection ratio compared with planar one. However, the associated large surface/volume ratio of nanostructured Si suffers from serious surface recombination as well as poor adhesion with organics in organic‐Si heterojunction solar cells, which leads to an inferior open‐circuit voltage (V_oc). Here, we develop a simple and effective method to suppress charge recombination as well as enhancing adhesion force between nanostructured Si and organics by incorporating a silane chemical, namely 3‐glycidoxypropyltrimethoxydsilane (GOPS). GOPS can chemically graft onto nanostructured Si and improve the aqueous organic wetting properties, suppressing surface charge recombination velocity dramatically. In addition, this chemically grafted layer can enhance adhesion force between organics and Si. In such a way, a record V_oc of 640 mV associated with a power conversion efficiency of 14.1% is obtained for organic‐nanostructured Si heterojunction devices. These findings suggest a promising approach to low‐cost and simple fabrication for high‐performance organic‐Si solar cells.     

同轴线波导接头的分析

本文给出了同轴线到一般导波结构间接头的分析模型，举例给出同轴线／径向波导接头的分析结论，与文献[2]的结论是完全一致的。     

NiFe/Ag/NiFe纳米结自旋晶体管研究

利用直流磁控溅射工艺和掩膜技术研制出新型NiFe/Ag/NiFe全金属自旋晶体管试样。该薄膜磁阻系数ΔR/R≥9%,全金属自旋晶体管试样集电极电流变化MC>587%(常温),且其性能随基极Ag层厚度减小而增强。全金属自旋晶体管具有电流放大、存贮及逻辑电路等功能,,有望替代现有的晶体管而应用于半导体大规模集成电路。     

Junction between amorphous germanium and monocrystal pSi

In the present investigation the electrical behaviour of SnO₂-ⁿ_pSi-aGe-Me (In, Al, Ag, and Cr) is presented. Almost ideal Schottky diode behaviour is exhibited in a narrow region of applied bias. The junction current at large external bias (V > 300 mV) is dominated by tunnelling and the associated barrier height of aGe on monocrystal Si agrees with values reported for metal-monocrystal Si. Presence of interface states becomes manifest from the I-V and C-V characteristics.     

Radial-Line/Coaxial-Line Stepped Junction (Short Papers)

A radial-line/coaxial-line junction having a step in the inner conductor in the coaxial aperture is considered. It is shown that the stepped junction may be modeled by an equivalent circuit obtained by a simple modification of that for the unstepped junction. Comparison of theoretical and experimental results has established this representation to be very accurate over a wide frequency range.     

Cross-Coupled Coaxial-Line/Rectangular-Waveguide Junction (Short Papers)

The analysis of a cross-coupled coaxial-line/rectangular-waveguide junction having dissimilar coaxal lines is presented. An equivalent circuit is deduced for the case where the TE/sub 10/ mode is the only propagating waveguide mode. Experimental/theoretical comparisons are also reported which show the analysis to be very accurate.     

p^＋—n^——n结的势垒分布

GaP:N绿色LED发光效率的提高有赖于对其结构参数的优化。根据载流子分布的连续性,由泊松方程自治求解,得出了半导体n^--n结势垒分布的计算方法。在此基础上,计入n^-区内的电位降,计算了商用光二极管p^ -n^--n结构的势垒分布,为整体结构的参数优化准备了必要的条件。     

A Y To /spl Delta/ Transformation of a Three-Way Hybrid Junction

A three-way power divider/summer in the Wilkinson configuration can be symmetrically fabricated in stripline if the Y resistive balancing network is replaced by a /spl Delta/ resistive network. Port-to-port isolation in a stripline circuit at 2 GHz exceeded 27 dB; loss was below 0.15 dB.     

GaInP/GaAs/Ge三结太阳电池辐照损伤效应及加固技术研究进展

文章首先重点介绍了国内外开展GaInP/GaAs/Ge三结太阳电池的电子、质子及其他辐射粒子或射线辐照实验的研究进展,然后从辐照损伤效应的仿真模拟研究、抗辐射加固技术、损伤预估方法等方面综述了GaInP/GaAs/Ge三结太阳电池辐照损伤效应及加固技术的研究进展,最后梳理了当前GaInP/GaAs/Ge三结太阳电池辐照损伤效应研究中亟待解决的关键技术问题,为深入开展GaInP/GaAs/Ge三结太阳电池辐照损伤效应实验方法标准制定、损伤机理分析、在轨寿命预估及抗辐射加固技术研究提供了理论指导和实验技术支持。     

不同集电结结构的AlGaInP/GaAs异质结双极晶体管

设计并制备了三种不同集电结结构的A lG aInP/G aA s异质结双极晶体管,计算给出了三种集电结能带结构。通过对三种HBT的直流特性测试表明,N pN型HBT因异质集电结的导带尖峰出现电子阻挡效应;N p iN型HBT集电结引入i-G aA s层能有效克服电子阻挡效应,同时还具有拐点电压Vknee小、开启电压Voffset小、击穿电压BVCEO大等优点,但由于i-G aA s层引入增加了基区电子扩散长度,使器件电流增益有所下降。     

Junction capacitance switches

The design of junction capacitance switches consisting of a combination of abrupt junctions is considered. Theoretical characteristics are calculated for ideally abrupt junctions. The possibilities of fabrication by alloying and epitaxial growth are briefly discussed.     

Electronic Properties and Junction Behavior of Polyanthranilic Acid/Metal Contacts

Polyanthranilic acid (PANA), a self-doped processible conducting polymer, was synthesized and used for the first time for fabrication of contacts with configurations of (Al, Ti, Sn metal)/PANA/indium tin oxide-coated glass. The current-voltage (I-V) characteristics were measured by using microprobe arrangements, and the diode performance parameters were extracted. The I-V characteristics of the aforementioned configuration exhibited a rectifying contact for the case of Al and Ti metal contacts but an ohmic contact for the case of Sn metal contact. The electroactivity of PANA was carried out in acidic solution, and film morphology was studied by using atomic force microscope. UV-Vis spectroscopic technique was used to obtain the optical bandgap of the polymer.     

Electrothermal Analysis for Super‐Junction TMOSFET with Temperature Sensor

For a conventional power metal–oxide–semiconductor field‐effect transistor (MOSFET), there is a trade‐off between specific on‐state resistance and breakdown voltage. To overcome this trade‐off, a super‐junction trench MOSFET (TMOSFET) structure is suggested; within this structure, the ability to sense the temperature distribution of the TMOSFET is very important since heat is generated in the junction area, thus affecting its reliability. Generally, there are two types of temperature‐sensing structures — diode and resistive. In this paper, a diode‐type temperature‐sensing structure for a TMOSFET is designed for a brushless direct current motor with on‐resistance of 96 mΩ·mm². The temperature distribution for an ultra‐low on‐resistance power MOSFET has been analyzed for various bonding schemes. The multi‐bonding and stripe bonding cases show a maximum temperature that is lower than that for the single‐bonding case. It is shown that the metal resistance at the source area is non‐negligible and should therefore be considered depending on the application for current driving capability.