微波数字复合基板金属化孔工艺方法

微波数字复合基板是将微波电路与数字电路集合在一起的新型复合多层基板,其体积的缩小实现了雷达天线系统的轻量化和小型化.在复合基板的制作过程中,金属化孔的可靠性是保证天线电性能指标的关键.主要介绍了微波数字复合基板中微盲孔孔金属化及提高金属化孔可靠性的工艺方法.     

参数可调滤波器的低频频谱分析仪

低频频谱分析仪主要针对振动和声音信号进行频谱分析 ,传统的档级滤波器式频谱分析仪因成本和技术的原因已经面临淘汰。作为替代 ,文章介绍了一种基于单片机和数字电位器的低频频谱分析仪 ,它以低成本和高灵活性实现了低频频谱分析仪的所有功能 ,并且在振动信号的频谱分析方面获得了应用 ,运行情况良好     

CIS积分时间在线自调节技术应用

接触式图像传感器(CIS)在无线射频识别(RFID)柔性基板纠偏控制器中负责获取柔性基板上特征标志线的图像,RFID标签生产过程中会用到不同材质或不同颜色的柔性基板,为了获取不同柔性基板的高质量特征标志线图像,以提高纠偏控制精度,提出一种利用CIS图像对比度作为反馈信号的积分时间在线自动调节技术.首先分析并给出了不同积分时间对获取实际图像信号产生的影响,接着介绍用可编程逻辑器件(CPLD)实现该技术的方法,给出了仿真验证结果,以及对柔性基板测试样本的应用测试结果.该技术已经实际用于某企业研制的RFID标签封装设备自动纠偏控制系统中.     

数模混合高速集成电路封装基板协同设计与验证

介绍了数模混合高速集成电路(IC)封装的特性以及该类封装协同设计的一般分析方法.合理有效的基板设计是实现可靠封装的重要保障,基于物理互连设计与电设计协同开展的思路,采用Cadence APD工具以及三维电磁场仿真工具实现了特定数模混合高速集成电路(一款探测器读出电路)的封装设计与仿真论证,芯片封装后组装测试,探测器系统性能良好,封装设计达到预期目标.封装电仿真主要包含:封装信号传输通道S参数提取、电源/地网络评估,探测器读出芯片封装体互连通道设计能满足信号带宽为350 MHz(或者信号上升时间大于1 ns)的高速信号的传输.封装基板布线设计与基板电设计协同分析是提高数模混合高速集成电路封装设计效率的有效途径.     

基于LXI总线多路信号源的设计与实现

该文介绍了一种多路信号源的实现方式。采用PLL技术产生高频信号,采用DDS技术产生小步进低频信号,使用FPGA技术产生噪声信号,基于LXI总线和DSP技术实现各功能电路的控制和信号处理。该文主要论述的内容包括三路信号源的方案设计、电路实现和测试结果分析。     

低温烧成多层陶瓷基板

低温烧成多层陶瓷基板被作为第五代电子元件组装用基板而受到极大重视。本文概述了该基板的开发情况,介绍了它的制造技术,扼要分析了这种基板的主要性能,简述了基板的应用情况。实践表明,要制成性能优异的基板,除了选择合适的材料,采用先进的工艺技术和进行严格操作外,还要解决多层基板高密度、高强度、高绝缘、降低膨胀系数以及控制收缩等许多技术问题。     

超光网的测试与应用

本文介绍了超光网技术在苏州分公司的测试与应用情况,验证了高频调制信号在有线网络传输的可行性,测试了QAM调制信号在1~3GHz频段内传输的频谱特性。通过自主研发降频器设备,实现了高低频信号的自主选择,并在机顶盒上实现了双频段节目的正常收视。     

超宽带技术在通信中的应用

如今信息数字化与通信技术飞速发展，低频、高带宽的超宽带技术恰恰符合这一发展需求，有着良好的发展前景。对超宽带通信的发射、接收信号模型、收发机系统结构以及一些主要特点做了较深入的分析，并介绍了它在通信中的发展过程和现状。     

陶瓷基板研究现状及新进展

近年来,电力机车、电动汽车和微波通信等行业发展迅速,系统所用的电子器件具有大功率、小尺寸、高集成和高频率等特点.为满足电子器件散热、密封和信号传输优良的需求,陶瓷基板以较高的热导率、与半导体材料相匹配的热膨胀系数、致密的结构和较高的机械强度等特性得到广泛的应用.首先综述了不同陶瓷基板材料的性能、发展历史和新进展,分析了各自的优缺点;然后综述了陶瓷基板的制备工艺,对多层共烧陶瓷技术进行了详细介绍,并简述了陶瓷基板的应用;最后指出了陶瓷基板的研究方向和面临的挑战.     

CSP及其基板技术

本文首先介绍了CSP的发展过程、常见CSP的种类以及CSP对基板的技术要求,并在此基础上对CSP基板技术作了分类介绍.文中涉及的CSP基板技术包括设计、图象转移、基材、铜箔、微孔互连、表面涂层、AOI、电测试等.     

An investigation of the DC and RF performance of InP DHBTs transferred to RF CMOS wafer substrate

This paper investigated the DC and RF performance of the InP double heterojunction bipolar transistors (DHBTs) transferred to RF CMOS wafer substrate.The measurement results show that the maximum values of the DC current gain of a substrate transferred device had one emitter finger,of 0.8μm in width and 5μm in length,are changed unobviously,while the cut-off frequency and the maximum oscillation frequency are decreased from 220 to 171 GHz and from 204 to 154 GHz,respectively.In order to have a detailed insight on the degradation of the RF performance,small-signal models for the InP DHBT before and after substrate transferred are presented and comparably extracted.The extracted results show that the degradation of the RF performance of the device transferred to RF CMOS wafer substrate are mainly caused by the additional introduced substrate parasitics and the increase of the capacitive parasitics induced by the substrate transfer process itself.     

温度对AlGaN/GaN HEMT电学性能的影响

研究了蓝宝石衬底AlGaN/GaN HEMT器件直流和微波性能随温度的变化。研究结果表明,器件直流性能随着温度升高逐渐下降,350°C时直流性能依然良好,从350°C冷却到室温后,器件直流特性除欧姆接触电阻改善外,其他都得到了恢复;微波测试表明,器件fT,fmax都随温度升高而下降,180°C时,fT从室温的11.6GHz下降为7.5GHz、fmax从24.6GHz下降为19GHz,通过外推得到350°C时的fT为3.5GHz,fmax为12GHz。证明了AlGaN/GaN HEMT具有良好的热稳定性,适合在高温下进行高频工作。     

一种新型高效收发组件的研究与设计

对多层微波数字复合基板和宽禁带高效电路进行了研究,并设计了一种基于高效宽禁带器件和多层微波数字复合基板技术的收发组件。该收发组件的发射功率大于10W,发射通道射频功率效率超过60％,大大高于传统收发组件的效率。     

Printed microinductors on flexible substrates for power applications

A low-profile microinductor was fabricated on a copper-clad polyimide substrate where the current carrying coils were patterned from the existing metallization layer and the magnetic core was printed using a magnetic ceramic-polymer composite material. Highly loaded ferrite-polymer composite materials were formulated, yielding adherent films with 4/spl pi/M/sub s//spl ap/3900 G at +5000 Oe applied DC field. These composite magnetic films combine many of the superior properties of high temperature ceramic magnetic materials with the inherent processibility of polymer thick films. Processing temperatures for the printed films were between 100/spl deg/C and 130/spl deg/C, facilitating integration with a wide range of substrates and components. The quality factor of the microinductor was found to peak at Q=18.5 near 10 MHz, within the optimal frequency range for power applications. A flat, nearly frequency independent inductance of 1.33 /spl mu/H was measured throughout this frequency range for a 5 mm/spl times/5 mm component, with a DC resistance of 2.6 /spl Omega/ and a resonant frequency of 124 MHz. The combination of printed ceramic composites with organic/polymer substrates enables new methods for embedding passive components and ultimately the integration of high Q inductors with standard integrated circuits for low profile power electronics.     

DC and RF performance of 0.25 μm p-type SiGe MODFET

The DC and RF performance of a 0.25 μm gate-length p-type SiGe modulation-doped field-effect transistor (MODFET) is reported. The hole channel consists of compressively strained Si_0.3Ge_0.7 layer grown on a relaxed Si_0.7Ge_0.3 buffer on a Si substrate. The combination of high-hole mobility, low-gate leakage current, and improved ohmic contact metallization results in an enhancement of the DC and RF performance. A maximum extrinsic transconductance (g(m_ext)) of 230 mS/mm was measured. A unity current gain cut-off frequency (fT) of 24 GHz and a maximum frequency of oscillation (f_max) of 37 GHz were obtained for these devices     

一种基于DDS技术的新型宽带雷达信号源的设计

AD9858是Analog Devices公司的一款高性能DDS芯片,可产生多种形式的信号,在对DDS原理以及AD9858器件研究的基础上,介绍了一种基于AD9858的宽带雷达信号源的设计方案,可输出单点频正弦信号、基带CHIRP信号、基带BPSK信号、射频CHIRP信号、射频BPSK信号。射频CHIRP信号由基带CHIRP信号经过倍频链转换到相应频段,射频BPSK由基带BPSK经过混频转换到相应频段。输出信号形式可由上位机通过USB接口灵活控制。     

A 9–31-GHz Subharmonic Passive Mixer in 90-nm CMOS Technology

A subharmonic down-conversion passive mixer is designed and fabricated in a 90-nm CMOS technology. It utilizes a single active device and operates in the LO source-pumped mode, i.e., the LO signal is applied to the source and the RF signal to the gate. When driven by an LO signal whose frequency is only half of the fundamental mixer, the mixer exhibits a conversion loss as low as 8–11 dB over a wide RF frequency range of 9–31GHz. This performance is superior to the mixer operating in the gate-pumped mode where the mixer shows a conversion loss of 12–15dB over an RF frequency range of 6.5–20 GHz. Moreover, this mixer can also operate with an LO signal whose frequency is only 1/3 of the fundamental one, and achieves a conversion loss of 12–15dB within an RF frequency range of 12–33 GHz. The IF signal is always extracted from the drain via a low-pass filter which supports an IF frequency range from DC to 2 GHz. These results, for the first time, demonstrate the feasibility of implementation of high-frequency wideband subharmonic passive mixers in a low-cost CMOS technology.     

一种短波有源天线供电转换器的设计

设计了一种短波有源天线供电转换器,利用直流信号和高频信号的频率差异,通过一条传输线路完成射频信号的传输和天线放大器的直流供电,根据射频器件的高频特性实现2路信号的隔离和复用,采用ADS射频仿真软件建立仿真模型。仿真结果显示在工作带宽内射频阻抗特性和直流电压平稳。制作了一台四通道短波有源天线供电转换器,在1．5～30 M Hz的工作频率范围内实测结果和仿真计算结果相吻合,可与宽带接收机实现良好的匹配。同时,供电转换器各通道之间幅度和相位一致性很好,还可满足一些有源阵列天线的需求。     

宽带隙立方氮化硼薄膜制备

报道了用偏压调制射频溅射方法制备宽带隙立方氮化硼(c-BN)薄膜的实验结果.研究了衬底负偏压对制备c-BN薄膜的影响.c-BN薄膜沉积在p型Si(100)衬底上,溅射靶为六角氮化硼（h-BN）,工作气体为Ar气和N2气混合而成,薄膜的成分由傅里叶变换红外谱标识.结果表明,在射频功率和衬底温度一定时,衬底负偏压是影响c-BN薄膜生长的重要参数.在衬底负偏压为-200V时得到了立方相含量在90%以上的c-BN薄膜.还给出了薄膜中的立方相含量随衬底负偏压的变化,并对c-BN薄膜的生长机制进行了讨论.     

A low damage, low contaminant plasma processing system utilizingenergy clean technology

A plasma processing system for ULSI device manufacturing using energy clean technology is proposed that is capable of subtle control of ion impact energy under very low pressure and magnetron enhancement. Careful and extensive probe measurements were carried out to determine the effects of magnetic field, plasma excitation frequency, DC-biasing of plasma confining cylinder (shield), DC-biasing of electrodes and secondary RF excitation on spatial distribution of potential. It was found that the substrate DC potential can be effectively controlled by DC-biasing or RF-biasing using an external DC power source or a secondary RF excitation, respectively. As a consequence, the wafer-surface damage induced by the high energy ions can be minimized by directly controlling the potential difference between plasma and substrate. The study also found that DC-biasing of the shield is very effective in minimizing the chamber material contamination, i.e., the contamination levels of both iron and copper atoms measured by total reflection X-ray fluorescence spectroscopy