后摩尔时代的基于一维纳米材料的CMOS技术

基于碳纳米管的场效应晶体管技术源于1998年,在随后的近10年间p型（空穴型）场效应晶体管的制备技术日趋完善,其性能全面超过相对应的硅基场效应晶体管．最近北京大学研究组关于高性能室温弹道n型（电子型）碳纳米管场效应晶体管的研究为基于碳纳米管的CMOS（complementary metal—oxide—semiconductor）技术的腾飞装上了另一个翅膀．特别是这种技术无需掺杂,加上碳纳米管特殊的几何和电子结构使得基于碳纳米管的CMOS技术有望突破传统微电子工艺所面临的一些根本性的困难,为下一步实现基于碳纳米管的纳电子电路的规模集成奠定了基础．     

光照和退火对非晶硅场效应管特性的影响

氢化非晶硅（ａ－Ｓｉ：Ｈ）场效应晶体管（ＦＥＴ）的特性对环境因素较为敏感，光照、湿度和温度等都会对其产生影响。该文介绍光照和退火引起的氢化非晶硅场效应晶体管场效应特性的变化。长时间使用ＡＭＩ标准光源光照和３５０℃以上的温度退火都引起了样品场效应特性的较大变化，光照２ｈ使得样品开启电压从６Ｖ增大到１９Ｖ，场效应特性曲线向栅压较大的方向平移，而４７０℃的高温退火则使该样品的场效应特性曲线形状发生了极大的变化，栅电压的控制作用减弱。最后根据ａ－Ｓｉ：Ｈ的价键模型对此进行了讨论。     

贝尔实验室半导体器件的研制

叙述了贝尔实验室有关半导体器件的研制工作，主要论述了早期半导体器件的开发，点接触晶体管和结型晶体管，场效应晶体管（ＦＥＴ），发光二极管（ＬＥＤｓ），里德二极管（ＩＭＰＡＴＴ），以及光生伏打电池等     

处理放大器的同步分离电路

本文介绍了一种高性能的电视同步分离电路;计算了自动增益控制闭环迴路方程;提出了作为压控电阻用于反馈迴路的场效应晶体管的选择原则.最后给出了典型场效应晶体管3DO_1F及3DJ6E的实测压控电阻特性.     

集成MOSFET跨导结构非线性的谐波分析法

MOSFET 金属氧化物半导体场效应晶体管跨导结构是全集成 MOSFET-C连续时间滤波器的基本电阻结构.本文根据导出的 MOSFET 伏安特性的傅里叶公式,提出了失配情况下 MOSFET 跨导结构非线性的谐波分析法,并给出了详细表格以供应用时参考.     

M－FET管的DC模型

本文在全面分析改进型场效应（Ｍ－ＦＥＴ）电路的基础上，提出Ｍ－ＦＥＴ管的ＤＣ模型，并用实验加以验证．     

M—FET管的DC模型

本文在全面分析改进型场效应（Ｍ－ＦＥＴ）电路的基础上，提出Ｍ－ＦＥＴ管的ＤＣ模型，并用实验加以验证。     

碳纳米管用于场效应晶体管的应用研究

 传统硅晶体管在微小化方面遇到瓶颈,碳纳米管作为一维量子材料,成为未来晶体管最具潜力的候选者。介绍了几种典型的碳纳米管场效应晶体管结构的基本工作原理及独特性能;着重介绍了近年来几种常见的碳纳米管场效应晶体管,并结合其结构与工作原理,论述了一系列技术革新和性能改进;总结了碳纳米管场效应晶体管未来需解决的几个重要问题。     

K5,5,p的点可区别的IE-全染色（p≥2 028）

图G的IE-全染色f是指对?u,v∈V（G）,使得f（u）≠f（v）的一个一般全染色,其中u,v相邻,V（G）是图G的顶点集.设f是图G的IE-全染色,图G的一个顶点x在f下的色集合C（x）是指由x及x的关联边的颜色所构成的集合（非多重集）.若图G的任意两个不同顶点的色集合不同,则f称为图G的点可区别的IE-全染色（简记为VDIETC）.利用色集合事先分配法、构造染色法及反证法探讨了完全三部图K_5,5,p（p≥2028）的点可区别的IE-全染色问题,确定了K_5,5,p（p≥2028）的点可区别的IE-全色数.     

DrugFET的研究（XⅢ）：四苯硼钠一烟碱FET的研制与应用

本文将离子敏感场效应晶体管（ＩＳＦＥＴ）与药物敏感膜相结合,研制成一种药物敏感场效应晶体管传感器（ＤｒｕｇＦＥＴ）。用四苯硼钠为电活性物质,邻苯二甲酸二辛酯为增塑剂,制成ｐｖｃ膜,对烟碱的线性范围为１．０×１０－２～２．０×１０－５ｍｏｌ／Ｌ,斜率为５７．５ｍｖ／ｐｃ,适宜ｐＨ范围为５．５～８．０,检出限为１．０×１０－６ｍｏｌ／Ｌ。用该传感器分析烟草中烟碱的含量,结果和分光光度法相一致。     

最小二乘拟合计算有机薄膜晶体管阈值电压的研究

通过制备了一个基于并五笨为有源层的顶栅底接触OTFT器件获取电流电压实验数据,并运用电流电压特性曲线理论拟合计算方法计算其阈值电压.研究发现,采用不同的拟合方法得到的阈值电压值有较大的差异.若选取转移特性曲线线性区距中心1/2范围内测试点进行最小二乘拟合计算出的阈值电压能减少采用其他拟合方法的固有不准确性,而且与其他方法得到阈值电压最接近.     

并 五 苯 晶 体 薄 膜 的 生 长

用物理气相沉积法在水平系统中生长有机半导体并五苯晶体薄膜. 用10～30 mg的源生长出20～30 mm²大小的适合特性测量和器件 制备的晶体薄膜. 利用TEM， SEM和X光透射电镜等仪器对并五苯晶体薄膜进行了测试分析.     

几种可溶性有机半导体材料的合成与器件表征

以6,13-并五苯二酮为原料,利用Grignard试剂进行加成反应,合成了4种6,13-取代的并五苯衍生物.产物经IR和MS进行了结构鉴定.产物进行了器件表征,对它们的迁移率和开关电流比因素进行了探讨.     

Ultralow-power organic complementary circuits

The prospect of using low-temperature processable organic semiconductors to implement transistors, circuits, displays and sensors on arbitrary substrates, such as glass or plastics, offers enormous potential for a wide range of electronic products. Of particular interest are portable devices that can be powered by small batteries or by near-field radio-frequency coupling. The main problem with existing approaches is the large power consumption of conventional organic circuits, which makes battery-powered applications problematic, if not impossible. Here we demonstrate an organic circuit with very low power consumption that uses a self-assembled monolayer gate dielectric and two different air-stable molecular semiconductors (pentacene and hexadecafluorocopperphthalocyanine, F16CuPc). The monolayer dielectric is grown on patterned metal gates at room temperature and is optimized to provide a large gate capacitance and low gate leakage currents. By combining low-voltage p-channel and n-channel organic thin-film transistors in a complementary circuit design, the static currents are reduced to below 100 pA per logic gate. We have fabricated complementary inverters, NAND gates, and ring oscillators that operate with supply voltages between 1.5 and 3 V and have a static power consumption of less than 1 nW per logic gate. These organic circuits are thus well suited for battery-powered systems such as portable display devices and large-surface sensor networks as well as for radio-frequency identification tags with extended operating range.     

氟化并五苯分子光谱和激发态的密度泛函理论研究

采用密度泛函理论(DFT)计算了氟化并五苯分子.在几何结构优化的基础上,对其进行频率分析得到了分子的红外光谱和拉曼光谱,并对谱线中的各峰值做了具体指认,同时得到了分子的HOMO-LUMO能隙2.02 eV,表明其是有机半导体材料.利用含时密度泛函理论(TDDFT)对其激发态计算,得到最低10个跃迁允许的单激发态,并分析了光谱的波长范围.     

安全操作系统研究

计算机系统安全问题的解决，要从应用程序、操作系统、计算机硬件3个层次来考虑，其中每一层的安全依赖下一层提供的安全机制来保护。首先介绍了从操作系统层次保护系统安全的相关问题；然后论述了安全操作系统的重要性；最后讲述了安全操作系统发展历史、操作系统提供的一系列安全机制、各种安全标准和安全操作系统的设计。     

Preparation and characteristics of flexible all-organic thin-film field-effect transistor

Much attention has been attracted to organic thin-film field-effect transistors (OTFFETs) in the past decades[1—4]. Because of their lower cost and easier preparation, OTFFETs are considered to be useful in driving liquid crystal displays (LCD) and organic light-emitting diodes (OLED). Furthermore, flexible OTFFETs will be one of the most useful electronic devices for flexible active matrix driving circuits. OTFFETs based on pentacene single crystal have been reported to be of g…     

ZnO/Cs2CO3双电子传输层有机太阳能电池

有机太阳能电池的异质结界面是影响其性能的一个重要因素.以氧化锌/碳酸铯作为双电子传输层,改善电子传输层与活性层的界面接触并提高电子传输能力.利用溶胶-凝胶法制备OSCs器件,通过优化的双电子传输层,使基于PTB7-Th:PC₇₁BM的OSCs器件的最高效率达到了8.08%,其相较于ZnO电子传输层器件提高了10.68%.实验表明,由于ZnO/Cs₂CO₃ ETLs具有最佳的表面形貌和光吸收,其填充因子、短路电流密度和电子迁移率都显著提升.这种ZnO/Cs₂CO₃双电子传输层为OSCs性能改善提供了新的思路.     

Room-temperature solid-state maser

The invention of the laser has resulted in many innovations, and the device has become ubiquitous. However, the maser, which amplifies microwave radiation rather than visible light, has not had as large an impact, despite being instrumental in the laser's birth. The maser's relative obscurity has mainly been due to the inconvenience of the operating conditions needed for its various realizations: atomic and free-electron masers require vacuum chambers and pumping; and solid-state masers, although they excel as low-noise amplifiers and are occasionally incorporated in ultrastable oscillators, typically require cryogenic refrigeration. Most realizations of masers also require strong magnets, magnetic shielding or both. Overcoming these various obstacles would pave the way for improvements such as more-sensitive chemical assays, more-precise determinations of biomolecular structure and function, and more-accurate medical diagnostics (including tomography) based on enhanced magnetic resonance spectrometers incorporating maser amplifiers and oscillators. Here we report the experimental demonstration of a solid-state maser operating at room temperature in pulsed mode. It works on a laboratory bench, in air, in the terrestrial magnetic field and amplifies at around 1.45 gigahertz. In contrast to the cryogenic ruby maser, in our maser the gain medium is an organic mixed molecular crystal, p-terphenyl doped with pentacene, the latter being photo-excited by yellow light. The maser's pumping mechanism exploits spin-selective molecular intersystem crossing into pentacene's triplet ground state. When configured as an oscillator, the solid-state maser's measured output power of around -10 decibel milliwatts is approximately 100 million times greater than that of an atomic hydrogen maser, which oscillates at a similar frequency (about 1.42 gigahertz). By exploiting the high levels of spin polarization readily generated by intersystem crossing in photo-excited pentacene and other aromatic molecules, this new type of maser seems to be capable of amplifying with a residual noise temperature far below room temperature.     

CVI-RMI法制备C/SiC复合材料的微观结构与弯曲性能

以T700炭纤维准三维编织针刺整体毡为预制体,在炭纤维表面CVI预沉积热解炭涂层,利用化学气相渗透-反应熔体浸渗法(CVI-RMI)制备C/SiC复合材料,观察材料的微观形貌,并探讨界面对弯曲性能的影响。研究结果表明:利用CVI-RMI联合工艺制备的C/SiC复合材料致密度高,开孔率较小(10%),基体分布均匀;材料弯曲强度达133 MPa,呈逐层破坏机制,表现出良好的假塑性;热解炭涂层与CVI-SiC基体减少了RMI工艺过程对炭纤维的损伤,且热解炭涂层调节了炭纤维与基体之间的界面结合状况,有利于纤维的拔出。