短沟道CMOS／SIMOX器件及电路的辐照特性研究

利用薄膜全耗尽ＣＭＯＳ／ＳＯＩ工艺成功地研制了沟道长度为１．０μｍ的薄膜抗辐照ＳＩＭＯＸＭＯＳＦＥＴ、ＣＭＯＳ／ＳＩＭＯＸ反相器和环振电路，Ｎ和ＰＭＯＳＦＥＴ在辐照剂量分别为３ｘ１０５ｒａｄ（Ｓｉ）和７ｘ１０５ｒａｄ（Ｓｉ）时的阈值电压漂移均小于１Ｖ，１９级ＣＭＯＳ／ＳＩＭＯＸ环振经过５ｘ１０５ｒａｄ（Ｓｉ）剂量的电离辐照后仍能正常工作，其门延迟时间由辐照前的２３７ｐｓ变为３２８ｐｓ。     

高开关比（I_（on）／I_（off））a－Si TFT

本文报道了采用倒置交错结构（Ｔａ／（Ｔａ２Ｏ５）ＳｉＮｘ／ｉｎ＋ａ－Ｓｉ／Ａ１）的ＴＥＴ矩阵研究结果．其关态电流（Ｉ_ｏｆｆ（－５Ｖ））在５—７×１０￣－１４Ａ（对Ｗ／Ｌ＝１０），开态电流Ｉ_ｏｎ（Ｚ０Ｖ）大于１０μＡ，Ｉ_ｏｎ／Ｉｏｆｆ在１０８量级，场效应迁移率可达０．７９ｃｍ２／Ｖ．ｓ．     

0．1μm栅长的CMOS电路门延迟为11．8Ps

０．１μｍ栅长的ＣＭＯＳ电路门延迟为１１．８Ｐｓ据《ＮＩＫＫＩＥＬＥＣＴＲＯＮＩＣＳ》１９９３年第１２—２０期报道，１９９３年１２月６～８日在美国召开的国际电子器件会议（ＩＥＤＭ）上，美国ＡＴ＆Ｔ贝尔实验室，ＩＢＭ公司，日本富士通研究所和东芝研究开发...     

GaAs表面及Al_xGa_（1－x）As／GaAsHBT外基区表面（NH_4）_2S／SiN_x钝化工艺研究

分析了ＡｌｘＧａ１－ｘＡｓ／ＧａＡｓＨＢＴ外基区表面复合电流及外基区表面复合速度对直流增益的影响，用光致发光（ＰＬ）谱和Ａｌ／ＳｉＮｘ－Ｓ／ＧａＡｓＭＩＳ结构Ｃ－Ｖ特性，研究了ＧａＡｓ表面（ＮＨ４）２Ｓ／ＳｉＮｘ钝化工艺的效果及其稳定性。结果表明，ＥＣＲ－ＣＶＤ淀积ＳｉＮｘ覆盖并在Ｎ２气氛中退火有助于改善ＧａＡｓ表面硫钝化效果的稳定性。在此基础上形成了一套包括（ＮＨ４）２Ｓ处理、ＳｉＮｘＥＣＲ－ＣＶＤ淀积及退火并与现有ＨＢＴ工艺兼容的外基区表面钝化工艺，使发射区面积为４×１０μｍ２的器件增益比钝化前提高了４倍，且６０天内不退化。     

0．2μmCMOS门阵列

０．２μｍＣＭＯＳ门阵列日本ＮＴＴ公司采用ＳＩＭＯＸ（ＳｉｌｉｃｏｎＩｓｏｌａｔｉｏｎｂｙＩｍｐｌａｎｔｅｄＯｘｙｇｅｎ）工艺研制成功０．２μｍＣＭＯＳ门阵列。产品特点是低功耗和高集成度，其功耗是０．５μｍＣＭＯＳ门阵列的１０倍。产品的电路元件由波长...     

GaInNAs/GaAs量子阱激光器的发展与未来

ＧａＩｎＮＡｓ是一种直接带隙半导体材料,在长彼长（１．３０和 １．５５μｍ）光通信系统 中具有广阔的应用前景．通过调节 Ｉｎ和 Ｎ的组分,既可获得应变 ＧａＩｎＮＡｓ外延材料,也可制 备ＧａＩｎＮＡｓ与ＧａＡｓ匹配的异质结构,其波长覆盖范围为０．９－Ｎ２．０μｍ．ＧａＩｎＮＡｓ／ＧａＡｓ 量子阱激光器的特征温度为 ２００ Ｋ,远大于现行 ＧａＩｎＮＡｓＰ／ＩｎＰ激光器的特征温度（Ｔ０＝５０ Ｋ）． ＧａＩｎＮＡｓ光电子器件的此优异特性,对于提高光纤通信系统的稳定性、可靠寿命具有特 别重要的意义．由于ＧａＩｎＮＡｓ和具有高反射率（高达９９％）ＡＩ（Ｇａ）Ａｓ／ＧａＡｓ的分布布拉格 反射镜（ＤＢＲ）可生长在同－ＧａＡｓ衬底上,因此它是长波长（１．３０和 １．５５ μｍ）垂直腔面 发射激光器（ＶＣＳＥＬ）的理想材料．垂直腔面发射激光器是光纤通信、互联网和光信号处理的 关键器件． ＧａＡｓ基的超高速集成电路（ＩＣ）已有相当成熟的工艺．如果 ＧａＩｎＮＡｓ－ＶＣＳＥＬ 与 ＧａＡｓ－ＩＣ相结合,将使光电集成电路（ＯＥＩＣ）开拓出崭新的局面．本文还报道我们课题 组研制高质量 ＧａＮＡｓ／ＧａＡｓ超晶格和大应变 ＩｎＧａＡｓ／ＧａＡｓ量子阱结构取     

GaAs低能Si^＋及SiF^＋离子注入研究

本文对３０ｋｅｖ Ｓｉ＾＋和分子离子ＳｉＦ＾＋注入半绝缘ＧａＡｓ的行为进行了研究对比。注入Ｓｉ＾２＋样品的Ｓｉ原子纵向分布与相同条件下用ＳＩＣＴ模拟程序理论计算出的分布相一致。经灯光９００℃１０″ＲＴＡ，电激活率可达６０％，电化学Ｃ－Ｖ测得的载流子纵向分布与注入态ＳＩＭＳ结果相同，可以获得近０．２μｍ的ＧａＡｓ有源层。而注入分子离子ＳｉＦ＾＋样品，虽注入层较浅，但灯光退火后，电激活率很低。因此，用     

GaAs中氧的SIMS相对灵敏度因子的测定

介绍了用离子注入标样测定ＧａＡｓ中氧的ＳＩＭＳ相对灵敏度因子的方法，并将实验数据进行离子计数─浓度，溅射时间─深度转换后求得的特征值（Ｃｍａｘ、Ｒｐ、△Ｒｐ等）与理论计算值进行比较，二者符合较好，其中Ｃｍａｘ的ＳＩＭＳ测量值同ＬＳＳ理论计算值和ＭｏｎｔｅＣａｒｌｏ模拟计算值之间的平均偏差分别为９％和２７％．最后，对几种ＧａＡｓ基的材料和器件进行氧的定量分析，获得了有益的结果．     

高选择和自终止多也氧化硅SOI技术研究

本研究了ｎ型硅阳极化的高选择和终止工艺，并将该工艺用于形成多孔氧化硅全隔离ＳＯＩ结构。采用这种ＰＩＰＯＳ（Ｆｕｌｌ Ｉｓｏｌａｔｉｏｎ ｂｙ Ｐｏｒｏｎｓ Ｏｘｉｄｉｚｄｅ Ｓｉｉｌｃｏｎ）技术在ｎ＾－／ｎ＾＋／ｎ＾－／衬底上形成的ＳＯＩ（Ｓｉｌｉｃｏｎ Ｏｎ Ｉｎｓｕｌａｔｏｒ）结构，其顶层硅岛厚度可控制在较广范围（从１００ｎｍ到数μｍ），且硅岛宽度可大于１００μｍ．ＸＴＥＭ结果显示顶层硅／氧     

LT1780/LT1781双RS232驱动器/接收器

Ｔ１７８０／ＬＴ１７８１双ＲＳ２３２驱动器／接收器具有单５Ｖ电源、低功耗（只有４０ｍＷ）、±１５ｋＶＥＳＤ保护（在ＲＳ２３２线端不需要昂贵的ＴｒａｎｓＺｏｒｂｓ）。只用０．１μＦ外部电容器便可工作在１２０ｋＢａｕｄ（对于负载ＲＬ＝３Ｋ,ＣＬ＝２５００ｐＦ）,２５０ｋＢａｕｄ（对于负载ＲＬ＝３ｋ,ＣＬ＝１０００ｐＦ）。ＬＴ１７８０／ＬＴ１７８１与ＥＩＡＲＳ２３２标准是完全一致的。它的输出能承受±３０Ｖ而不损坏。在关闭或断电条件下其驱动器和接收器的输出处于高阻抗态。ＬＴ１７８０／ＬＴ１７８１的应用包…     

含铕三元配合物的合成及发光机理研究

实验合成了用于白光LED的红光荧光粉—Eu-苯甲酰丙酮(BA)-邻菲啰啉(Phen)。通过红外光谱、紫外光谱、荧光光谱、荧光寿命和热重分析,对其结构与性能进行了表征。结果表明:配体与Eu发生配位;配合物的吸收主要源于配体的吸收;配合物在365nm紫外光激发下,在611nm处发出特征红光,表明配合物是一种可用于365nm波长紫外芯片的光致荧光粉;配合物的荧光寿命为5.033×10-4 s,量子产率为68.4%;配合物起始分解温度在250℃附近,满足白光LED的工作温度。同时,通过量子化学计算出配体的单重态与三重态能级,对配合物发光机理进行了探讨分析。     

Chain‐Length Dependence of Singlet and Triplet Exciton Formation Rates in Organic Light‐Emitting Diodes

The operation and efficiencies of molecular or polymer organic light‐emitting diodes depend on the nature of the excited species that are formed. The lowest singlet and triplet excitons display different characteristics that impact on the quantum yields achievable in the devices. Here, by performing correlated quantum‐chemical calculations that account for both the electronic couplings and energetics of the charge‐recombination process from a pair of positive and negative polarons into singlet and triplet excitons, we show that the formation rates for singlet over triplet excitons vary with chain length and favor singlet excitons in longer chains. Thus, in polymer devices, the resulting singlet/triplet fraction can significantly exceed the spin‐statistical limit.     

Material Crystallinity as a Determinant of Triplet Dynamics and Oxygen Quenching in Donor Polymers for Organic Photovoltaic Devices

This paper is concerned with the photophysics of triplet excitons in conjugated donor polymers, and their quenching by molecular oxygen. These photophysics are assayed by transient absorption spectroscopy, and correlated with X‐ray diffraction measurements of relative material crystallinity. Eleven different donor polymers are considered, including representatives from several classes of donor polymers recently developed for organic solar cell applications. Triplet lifetimes in an inert (nitrogen) environment range from <100 ns to 5 μs. A remarkably quantitative correlation is observed between these triplet lifetimes and polymer XRD strength, with more crystalline polymers exhibiting shorter triplet lifetimes. Given the broad range of polymers considered, this correlation indicates that material crystallinity is the dominant factor determining triplet lifetime for the polymers studied herein. The rate constant for oxygen quenching of these triplet states, determined from a comparison of transient absorption data under inert and oxygen environments, also show a correlation with material crystallinity. Overall these dependencies result in the yield of oxygen quenching of polymer triplet states increasing strongly as the crystallinity of the polymer is reduced. These photophysical data are compared with photochemical stability of these donor polymers, assayed by photobleaching studies of polymer films under continuous light exposure in an oxygen environment. A partial correlation is observed, with the most stable polymers being the most crystalline, exhibiting negligible oxygen quenching yields. These results are discussed in terms of the likely origins of the correlations between material crystallinity and photophysics, and in terms of their implications for the environmental stability of such donor polymers in optoelectronic devices.     

Efficient Persistent Room Temperature Phosphorescence in Organic Amorphous Materials under Ambient Conditions

Persistent emission with a long lifetime (>1 s) from organic materials can only be observed at a low temperature, because of the significant nonradiative deactivation pathway that occurs at room‐temperature (RT). If organic materials with persistent RT emission in air could be developed, they could potentially be utilized for a variety of applications. Here, organic host‐guest materials with efficient persistent RT phosphorescence (RTP) are developed by minimizing the nonradiative deactivation pathway of triplet excitons. The nonradiative deactivation pathway is dependent on both nonradiative deactivation of the guest and quenching by diffusional motion of the host. The rigidity and oxygen barrier properties of the steroidal compound used as the host suppressed the quenching, and the aromatic hydrocarbon used as the guest is highly deuterated to minimize nonradiative deactivation of the guest. Red‐green‐blue persistent RTP with a lifetime >1 s and a quantum yield >10% in air is realized for a pure organic material.     

Relaxation dynamics of photoexcitations in polydiacetylene films

The relaxation dynamics of photoexcitations in a polydiacetylene (poly-3BCMU) film was investigated by femtosecond time-resolved absorption spectroscopy. Spectral change due to several nonlinear optical processes, i.e. hole burning, Raman gain, and dynamic Stark effect, was observed. The difference absorption spectra of singlet and triplet excitons minus ground state were measured. The photoexcited singlet excitons relaxed to the self-trapped state with the time constant of 150±50 fs. The lifetime of the self-trapped excitons was 2.0±0.1 ps at 10 K and 1.5±0.2 ps at 290 K. The lifetime of the triplet excitons was much longer than several tens of picoseconds and was consistent with the lifetime of 18 μs obtained by nanosecond spectroscopy     

Morphological Tuning of the Energetics in Singlet Fission Organic Solar Cells

Effective singlet fission solar cells require both fast and efficient singlet fission as well as favorable energetics for harvesting the resulting triplet excitons. Notable progress has been made to engineer materials with rapid and efficient singlet fission, but the ability to control the energetics of these solar cells remains a challenge. Here, it is demonstrated that the interfacial charge transfer state energy of a rubrene/C₆₀ solar cell can be modified dramatically by the morphology of its constituent films. The effect is so pronounced that a crystalline system is able to dissociate and collect triplets generated through singlet fission whereas an as‐deposited amorphous system is not. Furthermore, a novel technique for studying the behavior of this class of devices using external quantum efficiency (EQE) measurements in the presence of a background light is described. When this method is applied to rubrene/C₆₀ solar cells, it is shown that triplet–triplet annihilation makes significant contributions to photocurrent in the amorphous device—enhancing EQE by over 12% at relatively low intensities of background light (4 mW cm^?2)—while detracting from photocurrent in the crystalline device. Finally, the conclusions on how the material system is affected by its morphology are strengthened by time‐resolved photoluminescence experiments.     

Effect of quenching of molecular triplet states in organic dye lasers

The effect of quenching of metastable triplet states upon the efficiency of organic dye lasers is considered in detail by solving the coupled differential equations describing the laser process. It is shown that specific quenching agents for excited triplet states can 1) cause a dramatic increase in the laser efficiency, 2) negate the previous requirements of very fast pumping sources, and 3) permit the use of dyes with relatively small fluorescence quantum yields. The addition of quenching agents that quench both singlet and triplet states (such as molecular oxygen) generally improves the efficiency although not as dramatically. Steady-state solutions were developed that lead to analytical expressions for the laser efficiency and the concentrations of the excited states as a function of time.     

Delayed luminescence in a molecularly doped polymer (TAPC in polycarbonate)

Decay of the delayed luminescence of 1,1-bis(di-4-tolylaminophenyl)cyclohexane, both doped into a polycarbonate binder and matrix-isolated in an MTHF glass, has been studied upon excitation with the 308 nm line of an excimer laser. Time-resolved emission spectra have also been recorded. In the early time regime, 30 ns < t < 10 μs, the decay of the emission, identified as delayed fluorescence rather than phosphorescence, follows a power-law characteristic of geminate pair recombination in a disordered medium. Singlet–singlet excitation fusion is considered to be the main pathway for geminate pair formation. Fusion of triplet excitations becomes important for e–h pair formation at long times only (10 μs < t < 10 ms). The rate of triplet–triplet encounters carries a time dependence characteristic of the random walk of excitations in a disordered solid.     

肿瘤的光动力诊断和光动力治疗的研究进展

HPD等光敏化剂可以有选择地潴留在肿瘤内，激光诱导出的特征光谱可用于肿瘤的光动力诊断。当用一定波长的激光照射光敏物质分子时，它可以从基态跃迁激发单态，通过系际交叉过渡到激发三重态。处于三重态的光敏化剂分子通过能量转移，使三重态的氧变成对肿瘤细胞具有毒化作用的单态氧，从而实现了肿瘤的光动力治疗。     

Exciton–Exciton Annihilation in Thermally Activated Delayed Fluorescence Emitter

Recent studies have demonstrated that in thermally activated delayed fluorescence (TADF) materials, efficient reverse intersystem crossing occurs from nonradiative triplet exited states to radiative singlet excited states due to a small singlet–triplet energy gap. This reverse intersystem crossing significantly influences exciton annihilation processes and external quantum efficiency roll‐off in TADF based organic light‐emitting diodes (OLEDs). In this work, a comprehensive exciton quenching model is developed for a TADF system to determine singlet–singlet, singlet–triplet, and triplet–triplet annihilation rate constants. A well‐known TADF molecule, 3‐(9,9‐dimethylacridin‐10(9H)‐yl)‐9H‐xanthen‐9‐one (ACRXTN), is studied under intensity‐dependent optical and electrical pulse excitation. The model shows singlet–singlet annihilation dominates under optically excited decays, whereas singlet–triplet annihilation and triplet–triplet annihilation have strong contribution in electroluminescence decays under electrical pulse excitation. Furthermore, the efficiency roll‐off characteristics of ACRXTN OLEDs at steady state is investigated through simulation. Finally, singlet and triplet diffusion length are calculated from annihilation rate constants.