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71.
The temperature dependence of capacitance-voltage (C-V) and the conductance-voltage (G/w-V) characteristics of (Ni/Au)/Al0.3Ga0.7N/AlN/GaN heterostructures were investigated by considering the effect of series resistance (Rs) and interface states Nss in a wide temperature range (79-395 K). Our experimental results show that both Rs and Nss were found to be strongly functional with temperature and bias voltage. Therefore, they affect the (C-V) and (G/w-V) characteristics. The values of capacitance give two peaks at high temperatures, and a crossing at a certain bias voltage point (∼3.5 V). The first capacitance peaks are located in the forward bias region (∼0.1 V) at a low temperature. However, from 295 K the second capacitance peaks appear and then shift towards the reverse bias region that is located at ∼−4.5 V with increasing temperature. Such behavior, as demonstrated by these anomalous peaks, can be attributed to the thermal restructuring and reordering of the interface states. The capacitance (Cm) and conductance (G/w-V) values that were measured under both reverse and forward bias were corrected for the effect of series resistance in order to obtain the real diode capacitance and conductance. The density of Nss, depending on the temperature, was determined from the (C-V) and (G/w-V) data using the Hill-Coleman Method.  相似文献   
72.
基于FPGA的PCI接口控制器设计与实现   总被引:2,自引:0,他引:2  
胡菲  卢益明 《电子科技》2006,(7):71-74,79
给出了一种基于FPGA实现PCI总线接口控制器的设计方案,从而解决了视频码流高速传输问题,使视频解码芯片能够实时解码.设计在Mode1Sim环境下对Verilog HDL源程序进行前仿真,在Xilinx ISE环境下进行逻辑综合、布局布线后下载到Xilinx公司生产的XC2V6000芯片内.在驱动和应用程序的配合下,FPGA实验板在33MHz时钟频率下,视频数据传输率达到42MB/s,数据传输效果很好,完全符合PCI总线的要求,为能够实时解码提供了高速码流.  相似文献   
73.
The silicide formation and the redistribution of Pt after deposition and after a heat treatment at 290 °C of Ni1−xPtx films on Si have been analysed by atom probe tomography assisted by femtosecond laser pulses. Two phases with different composition were found to form during deposition at room temperature: a NiSi layer with a relatively constant thickness of approximately 2 nm and a particle of Ni2Si. The shape of the Ni2Si particle is in accordance with nucleation followed by lateral growth formation. After heat treatment, two silicide phases Ni2Si and NiSi were found together with the Ni1−xPtx solid solution. The redistribution of Pt at the Ni1−xPtx/Ni2Si interface is a clear illustration of the snowplow effect. A segregation of Pt at the Ni2Si/NiSi interface has been observed and is attributed to interfacial segregation. The effect of the redistribution of Pt on the silicide formation is discussed.  相似文献   
74.
In this paper, the Geometric Optics (GO) method using the approximate ray paths coupled with the Computer Aided Tri-dimensional Interface Application (CATIA) meshing modeling are implemented to analyze the performance of electric large three-dimensional dielectric radome-enclosed antenna of arbitrary contour shape. The surfaces of the radome are approximated by planar triangular patches, the influences of various number of patches on power transmission coefficient and Insertion Phase Delay (IPD) via an ogive and a conical radome are discussed by the hybrid method. The simulation results indicate that computational error from planar triangular patches can limit in one percent, meeting the engineering application requirements.  相似文献   
75.
SDN北向接口是通过控制器向上层业务应用开放的接口,其目标是使得业务应用能够便利地调用底层网络资源和能力。文章首先介绍SDN北向接口的功能、分类及实现案例;进而以云计算资源管理平台为例分析SDN应用;最后在OpenStack开源框架下提出虚拟机迁移网络策略同步跟随场景的实现方案。  相似文献   
76.
This paper reports on an investigation of interface state densities, low frequency noise and electron mobility in surface channel In0.53Ga0.47As n-MOSFETs with a ZrO2 gate dielectric. Interface state density values of Dit ∼ 5 × 1012 cm−2 eV−1 were extracted using sub-threshold slope analysis and charge pumping technique. The same order of magnitude of trap density was found from low frequency noise measurements. A peak effective electron mobility of 1200 cm2/Vs has been achieved. For these surface channel In0.53Ga0.47As n-MOSFETs, it was found that η parameter, an empirical parameter used to calculate the effective electric field, was ∼0.55, and is to be comparable to the standard value found in Si device.  相似文献   
77.
We have fabricated a pentacene based phototransistor by employing a modified nanostructured SiO2 gate dielectric. The photosensing properties of the pentacene thin film transistor fabricated on n-Si substrate with nanostructured SiO2 as gate dielectric have been investigated. The photocurrent of the transistor increases with an increase in illumination intensity. This suggests that the pentacene thin film transistor behaves as a phototransistor with p-channel characteristics. The photosensitivity and responsivity values of the transistor are 630.4 and 0.10 A/W, respectively at the off state under AM 1.5 light illumination. The field effect mobility of the pentacene phototransistor was also found to be 2.96 cm2/Vs. The nanostructured surface of the gate possibly is the cause of the high-mobility value of the phototransistor due to light scattering from the increased surface area.  相似文献   
78.
通用集成电路卡(UICC)的USAT(USIM应用工具箱)的应用为电信增值业务搭建了一个广阔的平台。针对当前3GPP标准中任意时刻均只允许最多一个主动式指令处理,不允许多个指令并行处理的情况,对多个主动式指令并行处理进行研究,包括终端侧和UICC侧应执行的操作,为USAT的后续发展提供参考。  相似文献   
79.
史立原  谭金蓉 《电视技术》2014,38(6):58-60,79
对比了目前几种安卓电视智能升级方案,提出了一种在现有电视技术条件下,通过一个自定义接口完成安卓电视机芯智能升级的方案。该方法具有电视整机机芯升级简单、便捷、成本低、原有整机利用率高的优点。并以50个管脚的自定义接口为例,具体阐述了安卓电视机芯升级的软件、硬件解决方案。  相似文献   
80.
提出一种以太网通讯接口的设计方案,介绍了以太网通讯的特点,以太网控制器芯片DM9000A的特性、以太网硬件接口电路设计原理,及以太网接口的初始化、发送和接收流程。  相似文献   
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