GeSi／Si应变超晶格退火及离子注入研究

用深能级瞬态谱（ＤＬＴＳ）研究退火及离子注入对分子束外延生长的ＧｅＳｉ／Ｓｉ应变超晶格性质的影响，观察到３个与位错有关的深中心和１个表层内的深中心，退火和离子注入都使得这些深中心的浓度增加数倍，说明ＧｅＳｉ／Ｓｉ应变超晶格不适应做过多的热处理．同时测定Ｐｄ＋注入在ＧｅＳｉ／Ｓｉ超晶格的杂质能级为ＥＣ＝０．２８ｅＶ，与体Ｓｉ中的Ｐｄ杂质能级一致．     

GaAs中过渡族杂质Pd和Zr有关的深中心

采用结谱、光荧光等技术对Ｐｄ和Ｚｒ在ＧａＡｓ中的光学和电学性质进行了研究．在ＧａＡｓ：Ｐｄ中观测到三个能级，分别位于导带下０．４ｅＶ、０．６０ｅＶ和价带上０．６９ｅＶ．在ＧａＡｓ：Ｚｒ中也观测到三个能级，分别位于导带下０．４３ｅＶ和价带上０．３２ｅＶ和０．５５ｅＶ．基于深中心所表现出的Ｐｏｏｌｅ－Ｆｒｅｎｋｅｌ效应，讨论了一些中心对应的荷电态，对它们的俘获和对光致发光的影响也作了研究．结果表明：Ｐｄ和Ｚｒ在ＧａＡｓ中均不是有效的复合中心．     

新型Al金属化系统微波器件EB结的可靠性研究

对具有Ａｌ－Ｓｉ－Ｐｄ／ＴｉＮ／Ｔｉ／ＰｔＳｉ／Ｓｉ（样品Ａ）和Ａｌ－Ｓｉ－Ｐｄ／Ｔｉ／ＰｔＳｉ／Ｓｉ（样品Ｂ）两种新型金属化结构的微波管的ＥＢ结在不同温度、相同电流条件下进行了加速寿命试验，得到其中值寿命（ＭＴＦ）相差近一倍，激活能分别为０．９２和０．７９ｅＶ，并给出了在温度和电流应力下ＥＢ结反向击穿特性的变化规律     

Co、Ti／Si_（1－x）Ge_x薄膜快速退火固相反应结构和组分研究

本文首次研究金属Ｃｏ与分子束外延Ｓｉ１－ｘＧｅｘ单晶薄膜快速热退火（ＲＴＡ）固相反应，并对比了ＣＯ、Ｔｉ与ＳｉＧｅ固相反应时不同的反应规律实验采用ＲＢＳ、ＡＥＳ、ＸＲＤ、ＳＥＭ等分析和测试手段对样品的组分和结构等薄膜特性进行检测．实验发现，Ｃｏ／Ｓｉ０．８Ｇｅ０，２在６５０℃热退火后形成组分为Ｃｏ（Ｓｉ０，９Ｇｅ０．１）的立方晶系结构，薄膜具有强烈择优取向；９００℃处理温度，有ＣｏＳｉ２形成，同时Ｇｅ明显地向表面分凝．ＴｉＮ／Ｔｉ／Ｓｉ０．８Ｇｅ０．２固相反应时，８５０℃处理可以形成Ｔｉ（Ｓｉ１－ｙＧｅｙ     

氢等离子体对（Pt及其硅化物）／Si界面的杂质／缺陷态和势垒的影响

存在于（Ｐｔ及其硅化物）／Ｓｉ界面的深能级缺陷常常会影响器件的性能．本文主要讨论氢等离子体对（Ｐｔ及其硅化物）／Ｓｉ界面深能级杂质缺陷的钝化作用及对其Ｓｃｈｏｔｔｋｙ势垒的影响．     

TiN覆盖层和Co/Ti/Si三元固相反应改善超薄CoSi_2高温稳定性

本文研究不同金属薄膜结构形成的超薄ＣｏＳｉ２膜的高温稳定性．采用离子束溅射和反应磁控溅射技术制备Ｃｏ／Ｓｉ、ＴｉＮ／Ｃｏ／Ｓｉ、Ｃｏ／Ｔｉ／Ｓｉ、ＴｉＮ／Ｃｏ／Ｔｉ／Ｓｉ不同结构，在高纯氮气下进行快速热退火（ＲＴＡ），形成ＣｏＳｉ２薄膜．应用四探针薄层电阻测试、扫描电子显微镜（ＳＥＭ）、透射电子显微镜（ＴＥＭ）进行测试．实验结果表明：ＴｉＮ覆盖层和Ｃｏ／Ｔｉ／Ｓｉ三元固相反应都是有利于形成具有良好高温稳定特性的ＣｏＳｉ２薄膜的有效方法，有望应用于深亚微米接触和互连技术中．     

Ge_(0.4)Si_(0.6)/Si多量子阱与Ge/Si短周期超晶格样品中的深中心

用深能级瞬态谱（ＤＬＴＳ）研究了分子束外延生长的Ｇｅ０．４Ｓｉ０．６／Ｓｉ多量子阱与Ｇｅ／Ｓｉ应变超晶格样品中深能级中心的性质．在两种样品中都观测到两个多数载流子中心和一个少数载流子中心．在Ｇｅ０．４Ｓｉ０．６／Ｓｉ多量子阱样品中深中心Ｅ２的能级位置为ＥＣ－０．３０ｅＶ,Ｅ３的能级位置为ＥＣ－０．２２ｅＶ．并且在正向注入下随着Ｅ２峰的消失观测到一个少数载流子峰ＳＨ１,其能级位置为ＥＶ＋０．６８ｅＶ．在Ｇｅ／Ｓｉ应变超晶格中,深中心Ｈ１的能级位置为ＥＶ＋０．４４ｅＶ,深中心Ｈ２的能级位置为ＥＶ＋０．２４ｅＶ     

Ge0.4Si0.6／Si多量子阱与Ｇe／Si周期超晶格样品中的深中心

用深能级瞬态谱（ＤＬＴＳ）研究了分子束外延生长的Ｇｅ０．４Ｓｉ０．６／Ｓｉ多量子阱与Ｇｅ／Ｓｉ为超晶格样品中深能级中心的性质,在种样品中都观测到两个多数载流子中心和一个少数载流子中心,在Ｇｅ０．４Ｓｉ０．６／Ｓｉ多量子阱样品深中心Ｅ２的能级位置为ＥＣ－０．３０ｅＶ,Ｅ３的能级位置为Ｅｃ－０．２２ｅＶ,并且在正向注入下随着Ｅ２峰的消失到一个少数载流子峰ＳＨ１,其能级位置为ＥＶ＋０．６８ｅＶ,在Ｇｅ／     

离子／电子混合导体Cu_xMo_6S_（8－y）的性能研究

本文通过对工艺条件的控制，获得了铜系混合导体材料Ｃｕ２Ｍｏ６Ｓ７、７、Ｃｕ２Ｍｏ６Ｓ８．０及Ｃｕ４Ｍｏ６Ｓ８．０．ｘ射线衍射物相分析表明为Ｍｏ６Ｓ８结构的单相，并采用分析化学方法对其化学计量进行了分析，通过测试得到了三种混合导体的总电导率σ和离子电导率σｉ·当混合导体Ｃｕ２Ｍ０６Ｓ７、７与固体电解质Ｒｂ４Ｃｕ１６Ｉ７Ｃｌ１３复合后可改善其电化学性能，复合比为２：１时，总电导率σ和离子电导率σｉ可达７５（Ω·ｃｍ）－１和７×ｌ０－２（Ω·ｃｍ）－１。     

空间电荷限制电流法对a—Si：H隙态密度的测量

本文介绍了用于测量ａ－Ｓｉ：Ｈ隙态密度的空间电荷限制电流（ＳＣＬＣ）法，并报道了采用此方法对ＰＥＣＶＤ方法制备的ａ—Ｓｉ：Ｈ材料隙态密度的测量结果。对ｎ＋ａ—Ｓｉ：Ｈ／ａ—Ｓｉ１Ｈ／ｎ＋ａ—Ｓｉ：Ｈ结构的样品，测量得到费米能级上０．１６ｅＶ间的欧态密度分布为１０１５～１０１８（ｃｍ－３ｅＶ－１）。     

Diamond Like Carbon Film Deposited on Porous Silicon as Passivation Coating

By depositing diamond like carbon(DLC)film with radio frequency plasma chemical vapor deposition(RFPCVD)method,a new surface passivation technique for photoluminescence porous silicon(PS)has been studied.The surface microstructure and photoelectric properties of both porous silicon and DLC coated PS have been analyzed by using AFM,FTIR and PL spectrometers.The results show the DLC film with dense and homogenous nanometer grains can be deposited on the PS used as passivation coating as it can terminate oxide reaction on the surface of the PS.Furthermore,certain ratio of hydrogen existed in the DLC film can be improved to form hydride species on the DLC/PS interface as the centers of the luminescence so that the DLC coating is of benefit not only to the passivation of the PS but also to the improvement of its luminescent intensity.     

类金刚石薄膜对多孔硅发光的钝化作用

介绍了类金刚石薄膜对多孔硅发光的钝化作用.类金刚石薄膜隔绝了外界对多孔硅表面的影响,使硅氢键不易断裂,从而减少了非辐射复合中心,稳定了多孔硅的发光性能.通过在类金刚石薄膜中掺氮还可以进一步提高钝化效果,因为氮使多孔硅表面更多的悬空键被钝化形成Si-N键,从而提高了发光强度.     

晶态半导体中氢的行为

<正> 近年来,氢在晶态半导体中的作用受到愈来愈多的关注,主要是氢或其同位素不仅可以钝化半导体中广泛类别的深能级,还可钝化浅杂质;同时,氢的存在还在半导体中引入与氢有关的缺陷与深能级。另外,氢广泛存在于许多化学试剂及水中,其扩散系数又远大于其它许多杂质,因而氢普遍地存在于半导体之中,对半导体性质产生深刻影响。     

Hydrogen desorption and diffusion in PECVD silicon nitride. Application to passivation of CMOS active pixel sensors

Presented either as a source or as a barrier to hydrogen, plasma deposited silicon nitride can impact microelectronic device performances. The objective of this paper is to clarify the hydrogen behavior in silicon nitride in order to optimize film characteristics for each microelectronic application. A design of experiments methodology was used to statistically discriminate films properties which govern hydrogen diffusion and desorption from PECVD silicon nitride. Finally, we confirm, thanks to trials on CMOS active pixel sensor devices and dark current measurements, the role of the SiN passivation layer on Si remaining defect and we propose an optimized passivation stack.     

Hydrogen Passivation in Mc-Si for Solar Cells

The effect of hydrogen passivation on multicrystalline silicon (mc-Si) used for solar cells is described, and the mechanism of hydrogen diffusion and passivation is also investigated. Then, the hydrogen passivation processes applied in industries and research laboratories are introduced. Finally the existing problems and the prospects of hydrogen passivation are reviewed.     

Improving the Performance of SiGe Metal–Semiconductor–Metal Photodetectors by Using an Amorphous Silicon Passivation Layer

SiGe metal-semiconductor-metal photodetectors (MSM-PDs) with a thin amorphous silicon (a-Si:H) passivation layer have been fabricated by an ultrahigh-vacuum chemical vapor deposition (UHVCVD) system. It was found that the thin (30 nm) a-Si:H passivation layer could effectively suppress the dark current of SiGe MSM-PDs. As compared to the unpassivated devices, the dark current for devices with a-Si:H passivation layers was drastically reduced by 1.7 times 10⁵, and the photo-to-dark current ratio was enhanced by 1.33 times 10⁶. We attribute this result to the passivation effect of a-Si:H films on SiGe surfaces by hydrogen diffusion, which can compensate the dangling bonds on the SiGe surface.     

A new technique to quantify deuterium passivation of interfacetraps in MOS devices

The ubiquitous presence of hydrogen in the fabrication of complementary metal oxide semiconductor (CMOS) devices results in the passivation of most interface traps by hydrogen. In this letter, we show that this hydrogen cannot be completely replaced by deuterium through a one-step deuterium anneal process. Improved device reliability attributed to deuterium incorporation at the oxide/silicon interface is thus limited by the remnant hydrogen. To determine the deuterium passivation fraction, we propose a new technique that is based solely on electrical testing. Compared to other techniques such as secondary ion mass spectrum (SIMS), the new technique can be used to measure the deuterium passivation fraction in deep submicron MOS devices with very small testing areas     

Improvement of Hydrogenated Amorphous-Silicon TFT Performances With Low-$k$Siloxane-Based Hydrogen Silsesquioxane (HSQ) Passivation Layer

A low-dielectric-constant (low-k)-material siloxane-based hydrogen silsesquioxane (HSQ) is investigated as a passivation layer in bottom-gate hydrogenated amorphous-silicon thin-film transistors (a-Si : H TFTs). The low-k HSQ film passivated on TFT promotes the brightness and aperture ratio of TFT liquid-crystal display due to its high light transmittance and good planarization. In addition, the performance of a-Si : H TFT with HSQ passivation has been improved, compared to a conventional silicon nitride (SiN_x)-passivated TFT because the hydrogen bonds of HSQ assist the hydrogen incorporation to eliminate the density of states between the back channel and passivation layer. Experimental results exhibit an improved field-effect mobility of 0.57 cm²/Vmiddots and a subthreshold swing of 0.68 V     

High efficiency polycrystalline silicon solar cells using lowtemperature PECVD process

Conventionally directionally solidified (DS) and silicon film (SF) polycrystalline silicon solar cells are fabricated using gettering and low temperature plasma enhanced chemical vapor deposition (PECVD) passivation. Thin layer (~10 nm) of PECVD SiO₂ is used to passivate the emitter of the solar cell, while direct hydrogen rf plasma and PECVD silicon nitride (Si₃N₄) are implemented to provide emitter and bulk passivation. It is found in this work that hydrogen rf plasma can significantly improve the solar cell blue and long wavelength responses when it is performed through a thin layer of PECVD Si₃N₄. High efficiency DS and SF polycrystalline silicon solar cells have been achieved using a simple solar cell process with uniform emitter, Al/POCl₃ gettering, hydrogen rf plasma/PECVD Si₃N₄ and PECVD SiO₂ passivation. On the other hand, a comprehensive experimental study of the characteristics of the PECVD Si₃N₄ layer and its role in improving the efficiency of polycrystalline silicon solar cells is carried out in this paper. For the polycrystalline silicon used in this investigation, it is found that the PECVD Si₃N₄ layer doesn't provide a sufficient cap for the out diffusion of hydrogen at temperatures higher than 500°C. Low temperature (⩽400°C) annealing of the PECVD Si₃N ₄ provides efficient hydrogen bulk passivation, while higher temperature annealing relaxes the deposition induced stress and improves mainly the short wavelength (blue) response of the solar cells     

Al-enhanced PECVD SiNx induced hydrogen passivation in string ribbon silicon

The effectiveness of manufacturable gettering and passivation technologies is investigated for their ability to improve the quality of a promising Si photovoltaic material. The results of this study indicate that a lifetime enhancement of 30 μs is attained when a backside screen-printed aluminum layer and a thin film of SiN_x, applied by plasma-enhanced chemical vapor deposition (PECVD), are simultaneously annealed at 850°C in a lamp-heated belt furnace. Based on the results of this study, a model is proposed to describe the Al-enhanced SiN_x induced hydrogen defect passivation in String Ribbon silicon due to the simultaneous anneal. According to this model, three factors play an important role: i) the release of hydrogen from the SiN_x film into the substrate; ii) the retention of hydrogen at defect sites in silicon; and iii) the generation of vacancies at the Al−Si interface due to the alloying process which increases the incorporation of hydrogen and creates a chemical potential gradient which enhances the migration of hydrogen in the substrate. A PC1D device simulation indicates that screen-printed cell efficiencies approaching 16% can be achieved if the gettering and passivation treatments examined in this study are employed, the substrate thickness is reduced, and a high-quality surface passivation scheme is applied.