用GXRD和XPS分析离子注入层的表面结构

采用由金属蒸气真空弧(MEVVA)离子源引出的强来流脉冲钨离子对H13钢进行了离子注入表面改性研究。借助掠面X射线衍射(GXRD)和X射线光电子能谱(XPS)考察了注入表面层的相结构以及钨、铁、碳的化学状态。研究发现，表面的含碳化钨层比含铁、钨氧化层要厚，离子注入层中钨元素以替位钨和三氧化钨形式存在，铁元素以金属铁和三氧化二铁形式出现，而又各价态元素的原于比随深度变化。     

氮离子注入表面改性PBO薄膜及其性能

利用70keV能量的氮离子对聚苯并二噁唑(PBO)薄膜进行常温下离子注入表面改性,注入剂量(每平方厘米注入的氮离子数)从1×10~(15)N~+/cm~2到5×10~(16)N~+/cm~2。采用红外(FTIR)、拉曼(Raman)、光电子能谱(XPS)及原子力显微镜(AFM)对其表面结构、组成及形貌进行了表征。研究了氮离子注入剂量对PBO薄膜表面结构与性能的影响。结果表明:注入氮离子后,薄膜表面发生化学键的断裂和交联,近表面区域发生碳化。随氮离子注入剂量的增加,表面粗糙度增加,表面接触角从93°降低到60°,表面润湿性提高了35%,电导率提高到5.7×10~(-9)S/cm,比纯PBO薄膜增加了3个数量级。     

钇离子注入对不锈钢耐水溶液腐蚀改性研究

用电化学测量和表面分析方法研究了钇离子注入对３０４Ｌ奥氏体不锈钢耐水溶液腐蚀改性作用。结果表明，在适当的注入剂量下，注入试样在０．５ｍｏｌ／ＬＨ２ＳＯ４、０．６ｍｏｌ／ＬＮａＣｌ水溶液中的自腐蚀电位正移，自腐蚀电流密度下降至原来的１／４～１／６，击穿电位上升３０～５０ｍＶ。通过离于注入方式添加的钇以过饱和固溶形式均匀分布在不锈钢表面。试样表面层内Ｃｒ／Ｆｅ比值增加，含氧层厚度也增加。钇对不锈钢耐水溶液腐蚀改性主要是通过表面合金化和改变不锈钢表面层成分实现的。研究表明，注入剂量的变化对材料的改性效果具有一定的影响。     

表面硅烷交联改性超高分子量聚乙烯材料在干摩擦条件下的摩擦磨损性能研究

为进一步提高超高分子量聚乙烯(UHMWPE)的耐磨损性能,制备了表面硅烷交联改性UHMWPE材料。本文对这种表面改性UHMWPE材料在干摩擦条件下的摩擦磨损性能进行了初步研究。结果表明,其摩擦系数、磨痕宽度与未经改性的UHMWPE相比均有一定程度的降低,磨屑数量也减少,耐磨损性能明显提高。其原因归结于经硅烷交联改性后,UHMWPE材料表面硬度提高,润滑状况改善,使材料抗磨粒磨损和抗粘着磨损能力提高,从而导致其耐磨损性能明显提高。     

聚苯胺薄膜的离子束效应

本文采用离子注入掺杂技术，研究了全氧化态聚苯胺薄膜的离子束效应．‘４０ｋＶＫ＋离子束注入后，聚苯胺薄膜的电导率随着剂量的增加而迅速增加．当剂量为１×１０１７Ｋ＋／ｃｍ２时，电导率增加了８个数量级．ＦＴＩＲ光谱图显示了Ｋ＋离子注入使全氧化态聚苯胺中的醌亚胺结构发生还原反应．温差电流法测量表明，离子注入区呈现ｎ型半导体特性．四探针法测量了离子注入掺杂聚苯胺的电导率与温度的关系．本文还对离子注入掺杂全氧化态聚苯胺的导电机制进行了初步探讨．     

铒注入Si（100）的结晶和掺杂规律研究

研究了Ｓｉ（１００）注入铒后所形成的表面非晶层在不同退火温度下的固相外延结晶以及铒的迁移和掺杂规律。结果表明，表面非晶层先以基体单晶硅为晶种固相外延结晶，铒在晶体－非晶界面偏析，但当铒偏析聚集到一定浓度时则外延结晶停止，剩余损伤层变为多晶结构。在３５０ｋｅＶ的高剂量注入下，再结晶区域内的最大掺杂浓度随退火温度的增加而降低，但对１５０ｋｅＶ的低剂量注入，观察到８５０℃退火温度下掺杂浓度的反常增强。     

钛基体中离子注入钯的电催化性能

钛基体在能量40keV下,离子注入1×10^1^6～1×10^1^8Pd^+/cm^2.在30%的KOH溶液中,研究了这些电极对氢和氧析出的电催化性能.结果表明, 离子注入电极的催化活性明显地优于未注入的钛基体,并随着离子注入剂量的增大,催化活性增大. 由极化测量求得有关动力学参数.这些数据表明,用高剂量钯离子注入的钛电极, 其电化学性能与钯电极相似.根据AES和XPS数据,讨论了注入电极表面的组成     

稀土对玻璃纤维填充金属-塑料多层复合材料抗冲击磨损性能的影响

研究了稀土元素处理玻璃纤维填充金属－塑料多层复合材料在冲击载荷、干摩擦条件下的摩擦和磨损性能，并利用扫描电子显微镜（SEM）对磨损表面进行了观察和分析，结果表明，用稀土表面改性剂处理玻璃纤维表面，可以提高玻璃纤维与聚四氟乙烯之间的界面结合力，改善复合材料的界面性能，并有利于在偶件表面形成分布均匀、结合强度高的转移膜，使复合材料与偶件表面之间的对摩减轻，大幅度地降低了复合材料的磨损，从而使复合材料具有优良的摩擦性能和抗冲击磨损性能。     

N+离子注入聚对苯乙炔衍生物的非线性光学性能

以对甲氧基苯酚和溴代异戊烷为原料,用脱氯化氢反应制备可溶性聚[2-甲氧基-5-(3'-甲基)丁氧基]对苯乙炔(MMB-PPV),通过核磁氢谱(1HNMR)和红外光谱(FTIR)对产物分子的结构进行表征.用能量为15keV、剂量为3.8×1015～9.6×1016ions/cm2的氮正离子(N+)对MMB-PPV薄膜进行注入改性.紫外-可见吸收光谱(UV-Vis)显示,注入离子在MMB-PPV薄膜内部引入杂质能级,破坏了分子的共轭结构.随着注入剂量增加,吸收边逐渐向长波方向移动,且分子激发态和基态间的光学带隙由2.12eV减小至1.81eV.用简并四波混频(DFWM)技术研究了离子注入MMB-PPV薄膜的三阶非线性光学性能.结果表明,未注入薄膜的三阶非线性极化率(χ(3))值为7.1×10-10esu,随着注入剂量的增加,χ(3)值逐渐增大,当注入剂量达到3.8×1016ions/cm2时,χ(3)值提高到9.3×10-9esu,继续增加注入剂量,χ(3)值开始下降,当注入剂量为9.6×1016ions/cm2时,χ(3)值降低到1.5×10-10esu.对离子注入MMB-PPV薄膜χ(3)值变化的机理进行了探讨.     

氩等离子体后辉光区对聚四氟乙烯膜表面的优化改性

在理想管式反应器中, 采用Langmuir双电子探针和电子自旋共振(ESR)诊断技术分别定量测定了氩等离子体场中各活性物种的轴向分布, 并利用氩等离子体放电区及后辉光区对聚四氟乙烯(PTFE)进行了表面改性. 通过接触角测量、扫描电子显微镜和X 射线光电子能谱分析比较了改性前后常规及后辉光氩等离子体对PTFE表面结构及性能的影响. 结果表明, 氩等离子体中电子及离子浓度随轴向距离的增大迅速降低, 30 cm后接近于0, 而自由基浓度则降低缓慢, 40 cm处仍为初始浓度的96%. 氩等离子体放电功率、处理时间和气体流量强烈影响着PTFE表面润湿性的改善效果. 后辉光区因抑制电子和离子的刻蚀作用, 强化自由基反应, 使改性效果远优于常规氩等离子体. 经氩等离子体后辉光区短时间(30 s)处理后, PTFE表面化学成分发生了变化, F/C原子比从3.27降至2.30, O/C原子比从0.02增至0.09. 脱氟作用和含氧基团(如CO)的引入是有效改善PTFE表面润湿性的关键因素.     

XPS研究等离子体处理的聚苯乙烯表面结构

采用不同功率、时间在不同气氛下对聚苯乙烯(PS)基片进行了等离子体处理。通过 X-射线光电子能谱技术、谱图的拟合、差谱分析和 Ar~+刻蚀的剖面处理,研究了 PS 表面组成与结构变化,指出处理的 PS 表面可能接入 C-O、C-NH、C=O、COOH 和 O-?-O 基团,因而改变了材料特性。     

重氮偶合方法合成主链型光响应偶氮聚合物

提出了一种利用重氮偶合方法合成主链偶氮聚合物的新方法,合成了一种主链含有假芪型偶氮生色团的聚合物.对合成聚合物的结构、热性能以及光响应性能进行了详细表征.在线偏振激光的作用下,聚合物膜中的偶氮苯生色团发生光致取向,用偏振紫外-可见光光谱测量了此聚合物膜的二向色性,得到聚合物膜的取向有序度为0.03.用波长为488 nm,能量密度为150 mW/cm2的相干Ar+激光对聚合物膜照射1000 s,得到形貌规整的正弦波形表面起伏光栅,光栅的周期为900 nm,起伏深度为89 nm.     

Evaluation of nucleic acid duplex formation on gold over layers in biosensor fabricated using Czochralski-grown single-crystal silicon substrate

With a view to developing an economical and elegant biosensor chip, we compared the efficiencies of biosensors that use gold-coated single-crystal silicon and amorphous glass substrates. The reflectivity of light over a wide range of wavelengths was higher from gold layer coated single-crystal silicon substrates than from glass substrates. Furthermore, the efficiency of reflection from gold layers of two different thicknesses was examined. The thicker gold layer (100 nm) on the single-crystal silicon showed a higher reflectivity than the thinner gold film (10 nm). The formation of a nucleic acid duplex and aptamer–ligand interactions were evaluated on these gold layers, and a crystalline silicon substrate coated with the 100-nm-thick gold layer is proposed as an alternative substrate for studies of interactions of biomolecules.     

Bulk electrochemical etching of semiconductor single-crystal silicon in HF-containing solutions

Effect of the component composition of an HF-containing electrolytic aqueous solution on the polishing electrochemical etching of semiconductor single-crystal silicon was studied. Propanol-2, SV-1017, and NH₄F served as additional components of solutions used for this purpose. The conditions in which this process can be employed to form elements with 3D structure in microsystems devices were determined. An analysis of the results obtained led to an assumption that the hydrogen passivation of the surface of semiconductor single-crystal silicon is the rate-determining factor affecting the development of a bulk polishing electrochemical etching of this material. Because the process of polishing electrochemical etching of silicon wafers is preserved during approximately 20 min, the method is acceptable for formation of shallow grooves in microsystems devices.     

Electrochemical Production of Ultrathin Silicon Dioxide Films

Low-temperature synthesis of ultrathin (20 nm) SiO₂ films, by anodizing semiconductor single-crystal silicon wafers, is studied. Effects of physicochemical properties of electrolyte and single-crystal silicon on the films' dielectric characteristics are considered.     

旋涂-逐层自组装制备光响应性聚丙烯酸酯类偶氮聚电解质多层膜

偶氮聚电解质的静电逐层自组装是实现偶氮聚合物功能性的重要手段,是制备诸如光存储材料、光开关材料和非线性光学材料等的新途径.因此,光响应性偶氮聚电解质的静电逐层自组装已引起了人们的广泛关注.静电逐层自组装通常在水溶液中进行,即通过基材在在水溶液中的交替浸渍和逐层     

Specific features of the bulk etching of single-crystal semiconducting silicon in aqueous KOH solutions

Bulk chemical etching of single-crystal semiconducting silicon in aqueous alkaline solutions of KOH was studied at various solution temperatures, alkaline component concentrations, and microscopic amounts of a potassium ferricyanide additive. Specific effects of these factors on the process of silicon etching are explained by comparing the corresponding activation energies. The possibility of using alkaline aqueous solutions of KOH with a potassium ferricyanide additive for fabrication of elements in microsystem technology devices is assessed.     

A novel polycrystalline silicon temperature sensor

A test structure to determine the temperature variation of resistivity of undoped polycrystalline silicon layers within the range 300 °C – 900 °C has been produced. An Arrhenius plot yielded an activation energy of 1.28 eV, as compared to 1.18 eV for single-crystal silicon. It is shown that the value of 1.28 eV corresponds to the activation energy for the grain-boundary conduction. Hence the temperature variation of the resistivity of undoped polycrystalline silicon is dominated by the activation energy associated with the grain boundaries. The resistor structure has also been used as a temperature sensor for a rapid thermal processing system.     

Ar+激光激励Pb2的色散荧光谱

The dispersed fluorescence spectra of Pb_2 dimer were recorded from the excitation of Ar~+ laser in HPOR. By the detailed spectroscopic analysis for this well-resolved fluorescence spectra, the ground state of pb_2 molecule and one of its electronically excited state were assigned preliminarily to be X~1∑_g~+ and F′Ⅱ_u state respectively.The spectral constants of the X and F are ω_e″=108.5 cm~(-1),ω_e″X_e″ = 0.209 cm~(-1), ω_e′=152.4 cm~(-1), ω_e′X_e′=0.636 cm~(-1) and T_e=19818,1 cm~(-1)., respectively     

Initial stages of growth of poly(p-xylylene) coatings: AFM study

The morphology of poly(p-xylylene) ultrathin films prepared by vapor deposition polymerization on the surface of single-crystal silicon (100) and on the cleaved surface of mica at a substrate temperature of 20°C has been studied by atomic force microscopy. At the initial stage, the growth of the poly(p-xylylene) coating follows the island mechanism. Within the framework of pyramidal model of island growth, the mean diffusion length for monomer p-xylylene is calculated: For the single-crystal silicon, this parameter is 15 ± 3 nm; for the cleaved surface of mica, 9 ± 2 nm. The nature of the substrate and defects on its surface show a peculiar effect on the structure of the poly(p-xylylene) coating. Thus, at a low monomer flow, nucleation of polymer islands on the surface of silicon is predominantly homogeneous, whereas on the cleaved surface of mica, it is heterogeneous. A change in the monomer flow significantly affects the rate of nucleation of polymer islands.