MIM结构薄膜应变栅的工艺研究

阐述了采用直接沉积法制作MIM结构薄膜应变栅的工艺方法 ,对制备过程中所遇到的难点进行了分析并提出相应的解决方法 ,对所制作的薄膜应变栅式称重传感器进行了性能测试。     

高阻硅基GaN晶片上MIS栅结构GaN HEMT射频器件研制

5G 通信中3. 4~3. 6 GHz 是主要使用频段。GaN 射频器件由于高频、低功耗、高线性度等优势,满足5G 通信应用需求。文中在高阻硅基GaN 外延片上研制了AlGaN/GaN 高电子迁移率晶体管(High Electron Mobility Transistor, HEMT),并分析了金属鄄绝缘层鄄半导体(Metal-Insulator-Semiconductor,MIS)栅对器件直流和射频特性的影响。研究发现:相比于肖特基栅结构,MIS 栅结构器件栅极泄漏电流减少2~5 个数量级,漏极驱动电流能力和跨导提高10%以上;频率为3. 5 GHz 时,增益从1. 5 dB 提升到4. 0 dB,最大资用增益从5. 2 dB 提升到11. 0 dB,电流增益截止频率为8. 3 GHz,最高振荡频率为10. 0 GHz。     

多种栅结构SOI NMOS器件ESD特性研究

研究了不同栅结构对栅接地SOI NMOS器件ESD(Electrostatic discharge,静电放电)特性的影响,结果发现环源结构的SOI NMOS器件抗ESD能力最强,而环栅结构的器件抗ESD能力最弱,其原因可能与器件有缘区面积和电流分布有关。     

多层介质膜MIM薄膜二极管的I-V特性研究

制备了一种用于有源矩阵液晶显示的具有对称结构、较好 I-V特性对称性和较高电流通断比的 MIM薄膜二极管。采用了基于反应溅射的多层膜工艺制备其 Ta2 O5绝缘层。采用原子力显微镜 (AFM)对 Ta2 O5膜进行了表面分析 ,并对 MIM薄膜二极管的 I-V特性进行了测试。AFM分析结果表明 ,电子束蒸发 /反应溅射 /电子束蒸发法工艺制备的绝缘膜表面平整 ,膜层较致密 ;I-V特性测试结果显示 ,MIM-TFD的电流通断比约为 1 0 5,I-V特性曲线的非线性系数为 1 0 ,左右阈值电压分别为 6.3 V和 5 .8V,具有良好的对称性。该 MIM薄膜二极管的性能可以满足有源矩阵液晶显示的要求     

基于MIM结构等离子体波导定向耦合器

理论设计了带有扇环共振微腔的弯曲金属-介质-金属(MIM)波导结构,利用共振微腔结构控制表面等离子体波在扇环直角顶点处的定向传播。通过有限时域差分(FDTD)法计算带有扇环微腔结构的直波导透射率与波长关系,并计算扇环微腔结构与传播波导间的间隔对光学性质的影响,发现此微腔波导结构具有较高的透射率,可以在特定波长位置实现滤波效果。基于上述理论设计三路、四路弯曲波导结构,实现表面等离子体波在弯曲波导处的分束、全反射等定向传输特性。该结构具有极强的光束缚效应,在纳米尺度对光进行传输,解决了光信号的反射、传输问题,在光集成、光通讯、光信息处理等方面有较好的应用前景。     

Al/C60/Cu薄膜结构的电学性质

将C60薄膜沉积在Al上,制成了Al/C60结构的薄膜二极管。对Al/C60结构的肖特基结构与金属-绝缘层-半导体(MIS)结构的电学特性做了研究。Al/C60肖特基结构在偏压±2 V时的整流比为30,而Al/C60的MIS结构在偏压±2 V时整流比为100。在MIS结构中,AlOx的形成起着关键的作用。研究还发现,刚沉积好的薄膜二极管,其整流效应并不理想,在真空中经退火处理后,其性能得到增强。此二极管在空气中无封装情况下表现出高稳定性。     

用于声表面波高温传感应变传递的过渡层薄膜

声表面波(SAW)器件广泛应用于极端环境传感,硅酸镓镧(LGS)是常用高温压电晶体,但高温下应变胶因结合力导致应变传递效果不佳。该文研究了高温环境下应变传感的过渡层薄膜技术,提出了一种新的过渡层薄膜解决方案及其工艺技术,可实现高温应变胶水传递应变更稳定的效果。结果表明,采用溅射Al再氧化可显著提升LGS与高温胶的结合力,从而实现很好的应变传递,使用这种过渡层实现了500℃下超大量程(1 000με)测量。     

纳米MOSFET的多栅结构和应变硅纳米线结构

介绍了在进入22 nm技术节点后MOSFET器件的两个发展方向,即多栅结构和应变硅纳米线结构.首先通过分析特征长度与有效栅极数量的关系,表明多栅结构器件可以有效增强栅极对沟道的控制,抑制短沟道效应,接近理想的亚阈值斜率;然后分析了应变对能带结构的影响,从理论上论述了应变沟道可以显著提高载流子迁移率;最后介绍了悬浮硅纳米...     

柔性高温NiCr薄膜应变计研究

耐高温的NiCr薄膜应变计在航空、航天领域有广泛的需求。采用射频磁控溅射方法制备了NiCr薄膜,研究了溅射气压和衬底温度对NiCr薄膜电阻温度系数的影响规律,结果表明:当溅射气压为0.2 Pa,基片温度为400℃时,电阻温度系数最小为130.7×10^-6/℃。利用优化的工艺条件,在Hastelloy柔性合金衬底上制备了NiCr薄膜应变计,测试结果表明,所制备的NiCr薄膜应变计在各个温度下其电阻随着应变呈线性变化,其应变灵敏度(GF)因子随温度增加而增大,当温度超过200℃后,GF因子缓慢变化。温度为400℃时,GF因子达到3。实验得到的基于Hastelloy合金衬底的柔性薄膜应变计为高温应变测量提供了一种新的手段。     

氮化硅薄膜MIM电容器的制备与性能研究

在被釉氧化铝陶瓷基片上,采用真空电阻蒸发法和等离子体增强化学气相沉积法制备了Au/NiCr电极薄膜及氮化硅(SiNx)介质薄膜,并对薄膜进行光刻图形化,制成了Au/NiCr/SiNx/Au/NiCr结构的MIM电容器。研究了所制电容器的介电性能、介温性能和I-V特性等电学性能。结果表明:所得MIM电容器具有很低的介电损耗(1MHz时tanδ为0.00192)及很高的电压稳定性;在–55～+150℃的范围内其1MHz时的电容温度系数为258×10–6/℃;另外,其I-V特性曲线显示出较好的对称性,漏电流密度较低,可承受较高的电压。     

Evolution of grain structure in thin film reactions

In this paper, we examine, both experimentally and theoretically, the kinetics of formation and microstructure of product phases in thin film reactions, using the Nb/Al and Ti/Al systems as our prototypes. The results of calorimetry and microscopy studies are interpreted using simple kinetic and morphology models. In particular, the kinetic models employed here focus on the nucleation and growth components of the phase formation process and the morphology models provide a starting point for the classification of product grain structures. An erratum to this article is available at .     

YSZ/Al_2O_3复合薄膜高温绝缘层的研究

采用电子束蒸发、射频磁控溅射、等离子喷涂等方法,在镍基高温合金基底上制备YSZ(质量分数12%Y2O3稳定的Zr O2)、Al2O3复合薄膜结构绝缘层,并研究了复合薄膜结构绝缘层在室温到800℃范围内的绝缘特性,以及高温对复合薄膜晶体结构和表面形貌的影响。结果表明:晶态YSZ/非晶态YSZ/Al2O3结构绝缘层在室温下的绝缘电阻大于1.2 GΩ,在800℃大气环境下有150 kΩ左右的绝缘电阻。在室温到800℃范围内,随温度升高其绝缘电阻呈近指数下降的变化规律。经过在800℃大气环境中热处理8 h,YSZ的立方相结构未发生改变,Al2O3表面十分致密,表明该复合结构绝缘层薄膜具有良好的高温绝缘性能和稳定性。     

High efficiency low temperature grown Cu(In,Ga)Se2 thin film solar cells on flexible substrates using NaF precursor layers

We report a total‐area efficiency of 15.9% for flexible Cu(In,Ga)Se₂ thin film solar cells on polyimide foil (cell area 0.95 cm²). The absorber layer was grown by a multi‐stage deposition process at a maximum nominal process temperature of 420°C. The Na was added via evaporation of a NaF layer prior to the absorber deposition leading to an enhanced V_oc and FF. Growth conditions and device characterization are described. Copyright © 2011 John Wiley & Sons, Ltd.     

有源层溅射温度对非晶铟镓锌氧薄膜晶体管电学特性的影响

The effect of active layer deposition temperature on the electrical performance of amorphous InGaZnO （a-IGZO） thin film transistors （TFTs） is investigated. With increasing annealing temperature, TFT performance is firstly improved and then degraded generally. Here TFTs with best performance defined as ＂optimized-annealed＂ are selected to study the effect of active layer deposition temperature. The field effect mobility reaches maximum at deposition temperature of 150℃ while the room-temperature fabricated device shows the best subthreshold swing and off-current. From Hall measurement results, the carrier concentration is much higher for intentional heated a-IGZO films, which may account for the high off-current in the corresponding TFT devices. XPS characterization results also reveal that deposition temperature affects the atomic ratio and Ols spectra apparently. Importantly, the variation of field effect mobility of a-IGZO TFTs with deposition temperature does not coincide with the tendencies in Hall mobility of a-IGZO thin films, Based on the further analysis of the experimental results on a-IGZO thin films and the corresponding TFT devices, the trap states at front channel interface rather than IGZO bulk layer properties may be mainly responsible for the variations of field effect mobility and subthreshold swing with IGZO deposition temperature.     

Improved thermal stability in photochromism-based optically controllable organic thin film transistor

Thermally induced structural change in photoisomerization molecules is a serious obstacle to the development of optically controllable organic field-effect transistors (OFETs). This is because the thermal relaxation of molecular structures degrades photo-induced change in drain current and removes the memory function. To deal with this issue, a naphthopyran (NP) derivative, namely 3,13-dihydro-3-(4-triphenylaminyl)-3,13-diphenylbenzopyrano[5,6-a]carbazole (NP-TPAC) was tested that displays pseudo p-type photochromism at room temperature. The NP-TPAC-doped poly(triarylamine) (PTAA) film exhibited a reversible change in transistor properties; the drain current was reduced by ultraviolet (UV) and returned to its original value by visible (VIS) light irradiation. Importantly, no change in the drain current was observed at room temperature for more than 30 h under dark conditions. This was because the open-ring trans–trans (TT) isomer of NP-TPAC is thermally stable owing to the CH-π interaction and the steric force exerted by the phenyl ring of the carbazole unit onto the double bond responsible for the thermal back reaction. In other words, the thermal stability of photochromism-based optical devices can be greatly improved by adopting an appropriate molecular design.     

薄膜型光纤温度传感器的膜系设计

纳米薄膜与光纤的结合为新型感测提供了各种潜在可能.为了分析温度敏感薄膜的膜系设计及其对光纤温度传感器传感特性的影响,根据光学薄膜理论和光纤传感器的温度感测原理,探讨了光纤温度传感器中敏感薄膜的膜系设计,并构建了薄膜型光纤传感器的温度传感特性模型.以测试系统的参数、性能以及其对干涉光谱的要求为基础,设计了对称性较好的法布...     

薄膜红外探测器的研究

介绍了薄膜热电偶探测器的研究,讨论了薄膜热电偶探测器的结构对探测器响应特性的影响.     

退火温度对WO3薄膜结构及气敏性能的影响

采用直流磁控溅射法制备了WO3薄膜,并在350~550℃时对薄膜进行退火处理,研究了退火温度对薄膜结构及气敏性能的影响。结果表明:退火前及350℃退火后的薄膜为非晶态,450℃和550℃退火后的薄膜为WO3–x型晶态;随退火温度的提高,薄膜厚度增加,晶粒度增大。550℃退火后薄膜的厚度,较450℃退火后薄膜厚30nm,晶粒度相差8nm;450℃和550℃退火后的薄膜,在150℃时对体积分数为0.05%的NO2的灵敏度接近于22。