低损耗、高Q_m值Pb(Nb_(2/3)Mn_(1/3))O_3-Pb(Sb_(2/3)Mn_(1/3))O_3-PZT材料

研究了组分变化及掺杂对四元系 Pb( Nb2 /3Mn1 /3) O3- Pb( Sb2 /3Mn1 /3) O3- PZT压电材料性能的影响 ,发现 Zr/Ti比值在准同型相界附近该材料有最大的压电常数 d33,而机械品质因数 Qm 值较小 ;Zr/Ti比偏离该相界时则机械品质因数 Qm 升高 ,相应的压电常数 d33减小。通过改变 Pb( Nb2 /3Mn1 /3) O3、Pb( Sb2 /3Mn1 /3) O3两组分的含量及掺入 Sr、Ce等杂质 ,获得的材料介电损耗为 0 .14 % ,机械品质因数为 2 3 4 1,压电常数为 2 16p C/N。     

Pb（Y1／2Nb1／2）O3—PbTiO3—PbZrO3压电陶瓷相图研究

为了绘出Ｐｂ（Ｙ１／２Ｎｂ１／２）Ｏ３－ＰｂＴｉＯ３－ＰｂＺｒＯ３（ＰＹＮ－ＰＴ－ＰＺ）三元系铁电陶瓷材料的相图，以便对该系列材料的压电、介电性能有一个总体的认识，作者在参考有关文献的基础上，首先绘制出三元系材料的假想相图，然后按照一定的方法进行实验，逐步确定了该三元系实际的相图，并且对相图上某些区域的材料组成进行了较深入的实验研究，发现它们具有良好的压电、介电性，这表明该系列材料有较好的应用前景     

低损耗、高Qm值Pb(Nb2/3Mnl/3)O3-Pb(Sb2/3Mnl/3) O3-PZT材料

研究了组分变化及掺杂对四元系Pb(Nb2/3Mn1/3)O3-Pb(Sb2/3Mn1/3)O3-PZT压电材料性能的影响,发现Zr/Ti比值在准同型相界附近该材料有最大的压电常数d33,而机械品质因数Qm值较小;Zr/Ti比偏离该相界时则机械品质因数Qm升高,相应的压电常数d33减小.通过改变Pb(Nb2/3Mn1/3)O3、Pb(Sb2/3Mn1/3)O3两组分的含量及掺入Sr、Ce等杂质,获得的材料介电损耗为014%,机械品质因数为2341,压电常效为216 pC/N.     

xPb(Y_(1/2)Nb_(1/2))O_3-(1-x)Pb(Zr_(1/2)Ti_(1/2))O_3铁电陶瓷性能研究

系统地研究了 x Pb(Y1 / 2 Nb1 / 2 ) O3- (1- x) Pb(Zr1 / 2 Ti1 / 2 ) O3三元系铁电陶瓷材料 ,测量并计算了不同组分时的压电常数 (d33 )、介电常数 (εT3 3/ ε0 )、机电耦合系数 (kp、k31 )、以及弹性柔顺系数 (s E1 1 、s E1 2 、s E3 3 ) ,对 0 .0 7Pb(Y1 / 2Nb1 / 2 ) O3- 0 .93Pb(Zr1 / 2 Ti1 / 2 ) O3材料 ,d33 为 32 7× 10 - 1 2 C/ N,介电常数 εT3 3/ ε0 为 135 0 ,机电耦合系数 kp 大于 0 .6 ,弹性常数 SE1 1 和 SE3 3 均大于 17× 10 - 1 2 m2 / N。实现发现 ,当 x大于 0 .5 5时 ,x Pb(Y1 / 2 Nb1 / 2 ) O3- (1- x) Pb(Zr1 / 2 Ti1 / 2 ) O3不再是铁电材料     

(Na_(1/2)Bi_(1/2))TiO_3-SrTiO_3无铅压电陶瓷的介电、压电性能

研究了 (Na1 / 2 Bi1 / 2 ) Ti O3- Sr Ti O3二元系无铅压电陶瓷的介电、压电性性。Sr2 的引入对 NBT材料的常温介电系数、铁电相与反铁电相转变温度 TF A(180°C)以及居里温度 TC(30 0°C)的影响都不大 ,但却较大幅度地降低了 NBT材料的高矫顽场 ,从而使极化相对容易。(Na1 / 2 Bi1 / 2 ) Ti O3- Sr Ti O3二元系的压电性能参数 d33和 kt分别达到 10 0 p C/N和 0 .45     

低损耗、高Qm值Pb（Nb2／3Mn1／3）O3—Pb（Sb2／3Mn1／3）O3—PZT材料

研究了组分变化及掺杂对四元系Pb(Nb2/3Mn1/3)O3-Pb(Sb2/3Mn1/3）O3－PZT压电材料性能的影响,发现Zr/Ti比值在准同型相界附近该材料有最大的压电常数d33,而机械品质因数Qm值较小;Zr/Ti比偏离该相界时则机械品质因数Qm升高,相应的压电常数d33减小。通过改变Pb(Nb2/3Mn1/3)O3、Pb(Sb2/3Mn1/3)O3两组分的含量及掺入Sr、Ce等杂质,获得的材料介电损耗为0.14%,机械品质因数为2341,压电常数为216pC/N。     

掺杂的PNL-PFS-PZT铁电陶瓷性能研究

通过对几种不同的样品压电特性、机械品质因数和介电温谱等特性的对比和分析 ,研究了Pb (Li1/4Nb3 /4 )O3 Pb (Fe1/3 Sb2 /3 )O3 PbTiO3 PbZrO3 四元系陶瓷在不同配比和掺杂下的机电性能 ,发现该系列样品具有较高的压电常数 (可达 3 4 0× 10 -12 C/N)和介电驰豫温谱。文中还对该系列陶瓷的烧成工艺进行了一定的实验和对比 ,以寻找其最佳的烧成工艺。     

BiFeO_3改性Bi_(1/2)Na_(1/2)TiO_3-BaTiO_3基陶瓷电性能

采用固相反应法制备了新型(0.95–x)Bi1/2Na1/2TiO3-0.05BaTiO3-xBiFeO3(x=0~0.09)系无铅压电陶瓷,研究了BiFeO3掺杂量对其晶体结构、介电及压电性能的影响。结果表明:在所研究的组成范围内陶瓷均能形成纯钙钛矿型固溶体。介温曲线(10kHz)显示该陶瓷体系具有明显的弥散相变特征。该陶瓷体系的压电性能较Bi1/2Na1/2TiO3-BaTiO3陶瓷(d33=125pC/N)有较大提高,当x=0.05时,具有最佳的压电性能:d33=142pC/N,kp=0.29;此时εr=891,tanδ=0.046,Qm=110。     

xPb（Y1／2Nb1／2）O3—（1—x）Pb（Zr1／2Ti1／2）O3铁电陶瓷性能研究

系统地研究了xPb(Y1/2Nb1/2)O3-(1-x)Pb(Zr1/2Ti/2)O3三元系铁电陶瓷材料,测量并计算了不同组分时的压电常数(d33)、介电常数(εT33/ε0)、机电耦合系数(kp、k31)、以及弹性柔顺系数(sK11、sE12、sK33),对0.07Pb(Y1/2Nb1/2)O3-0.93Pb(Z[1/2Ti1/2)O3材料,D33为327×10-12C/N,介电常数εT33/ε0为1350,机电耦合系数kp大于0.6,弹性常数SE11和SE33均大于17×10-12m2/N.实现发现,当x大于0.55时,xPb(Y1/2Nb1/2)O3-(1-x)Pb(Zr1/2T11/2)O3不再是铁电材料.     

Bi1/2(Na1-xLix)1/2TiO3压电陶瓷的性能和微结构

利用传统陶瓷工艺制备了Bi1/2(Na1-xLix)1/2TiO3(简写BNLT100x,其中x为摩尔含量)系无铅压电陶瓷,研究了该陶瓷的微结构、压电和介电性能。X-射线衍射分析(XRD)结果表明,在x=0~0.20时,Bi1/2(Na1-xLix)1/2TiO3陶瓷为单相三方晶系钙钛矿结构;在x=0.30时,会有影响压电性能的第二相产生。扫描电镜(SEM)结果表明,Li含量越高,陶瓷的烧结温度越低,Li促进了晶粒特定方向的生长;在x=0.15时,压电系数d33达极大值109 pC/N;同时研究了极化工艺条件对材料压电性能的影响。     

Experimental Determination and Thermodynamic Modeling of the Sn-Rich Corner of the Ternary Ni-Pd-Sn Phase Diagram at 250°C

The Sn-rich portion of the phase diagram for the Ni-Pd-Sn ternary system was preliminarily obtained by interpolation of the three constituent binary systems using the Muggianu method. Based on this proposition, 23 Ni-Pd-Sn alloys were prepared and annealed at 250°C. The annealed alloys were analyzed by scanning electron microscopy, electron probe microanalysis, electron backscatter diffraction, and x-ray diffraction. All the binaries adjacent to the Sn-rich corner (i.e., PdSn₄, PdSn₃, PdSn₂, and Ni₃Sn₄) were found to have remarkable ternary solubility. The experimental results presented herein, together with a thermodynamic interpolation of the ternary system based on the results from the binary systems, were used to calculate the ternary phase diagram using the calculation of phase diagrams (CALPHAD) method. A substitution model was used to describe the Gibbs free energies of the liquid and solid solution phases, and a sublattice model was used to describe intermetallic compounds. A consistent set of thermodynamic parameters was obtained, ultimately leading to a better fit between the calculated results and the experimental data for this system.     

YVO4相图的研究

本文对钒酸钇的相图进行了系统的研究,详细地分析了钒酸钇熔体体系的二元相图、三元相图以及一些中间体系的相图;对比分析了相图对晶体生长的作用．并对用Ｃｚ法生长钒酸钇的过程中出现的黑相进行了物相分析,认为出现黑相的原因是生长过程中钒的变价和挥发造成的．     

Thermodynamic modeling of the Au-In-Sb ternary system

The phase diagram of the Au-In-Sb ternary system is of importance in predicting the interface reaction between In-based solders and the Au substrate. Using the calculated phase diagram method and based on experimental data of thermodynamic properties and phase boundaries, the Au-Sb binary system was assessed, and the In-Sb binary system was revised. On the basis of the constituent binary systems, Au-Sb, In-Sb, and Au-In, the Au-In-Sb ternary system was modeled. Several isothermal and vertical sections were calculated, among which the one at 500 K reproduces the experimental diagram well.     

Phase Equilibria in the Sn-Rich Corner of the Ni-Sb-Sn System

Phase equilibria in the ternary Ni-Sb-Sn system are of interest for high-temperature soldering, both considering ternary alloys as solder materials themselves or as the basis for understanding the reactions between Sb-Sn-based solders and Ni-based substrates. Therefore, the Sn-rich corner of the ternary Ni-Sb-Sn phase diagram with Sn content of more than 75 at.% was investigated by a combination of powder x-ray diffraction (XRD), differential thermal analysis (DTA), and electron probe microanalysis (EPMA). Ternary phase equilibria and phase compositions of the respective equilibrium phases were determined within the isothermal section at 200°C, and two isopleths were constructed for constant Sn contents of 80 at.% and 85 at.%. The experiments were supported by CALPHAD-type calculations of this ternary system to yield a consistent reaction scheme which shows four invariant ternary transition reactions in this composition range. A liquidus projection is presented, accompanied by the corresponding Scheil diagram.     

Thermodynamic assessment of the Sn-Co lead-free solder system

The Sn-Co-Cu eutectic alloy can be a less expensive alternative for the Sn-Ag-Cu alloy. In order to find the eutectic solder composition of the Sn-Co-Cu system, the Sn-Co binary system has been thoroughly assessed with the calculation of phase diagram (CALPHAD) method. The liquid phase, the FCC and HCP Co-rich solid solution, and the BCT Sn-rich solid solution have been described by the Redlich-Kister model. The Hillert-Jarl-Inden model has been used to describe the magnetic contributions to Gibbs energy in FCC and HCP. The CoSn₂, CoSn, Co₃Sn_{2_}β, and Co₃Sn_{2_}α phases have been treated as stoichiometric phases. A series of thermodynamic parameters have been obtained. The calculated phase diagram and thermodynamic properties are in good agreement with the experimental data. The obtained thermodynamic data was used to extrapolate the ternary Sn-Co-Cu phase diagram. The composition of the Sn-rich eutectic point of the Sn-Co-Cu system was found to be 224°C, 0.4% Co, and 0.7% Cu.     

MP3播放系统的设计与实现

本文介绍了用PT84 0 2设计MP3多功能播放器的一种方法 ,着重论述了设计中用到的一些器件及其功能 ,给出了PT84 0 2在该系统中的应用原理图和 84 0 2初始化及FLASH存储器的软件设计流程图。     

Effects of In and Sb doping in LPE growth thermodynamics and in GaAs layer qualities

We have experimentally determined the distribution coefficients of In and Sb in liquid phase epitaxially (LPE) grown GaAs at several different temperatures and found them to be consistent with the values calculated from the pseudobinary phase diagram of the ternary system at a dilute In or Sb concentration. Both In and Sb are found to be effective in reducing the dislocation densities in the LPE grown GaAs epi-layers. Studies of the phase diagram and the surface morphology indicate that Sb is more effective than In. Based on the results from the surface morphology, x-ray broadening and etch pit density (EPD) data, the optimal Sb concentration was 2–3 × 10¹⁹ cm⁻³.     

Ternary phase relations of the chalcopyrite compound CuGaSe2

The ternary Cu-Ga-Se phase diagram has been determined by DTA and x-ray analysis. In addition to two ternary solid solutions based on the binary compounds Cu_2.xSe and Ga₂Se₃, only one ternary phase, the chalcopyrite CuGaSe₂ (peritectic m.p. 1030°C), was encountered. The liquidus contains two regions of liquid immiscibility, one which extends from the Cu-rich (Cu, Se) binary liquid immiscibility to the Ga-rich (Ga, Se) binary immiscibility, and the other which is a minor extension of the Se-rich (Cu, Se) binary liquid immiscibility. The liquidus maxima include those at the binary boundaries: Cu (1087°C), Cu₆₇Se₃₃ (1148°C), GaSe (960°C); and a ternary liquidus maximum at Cu₁₉Ga_28.5Se_52.5 (1112°C), the maximum melting point of a solid solution based on the defect-zincblende phase of Ga₂Se₃. The primary phase fields are identified and the crystal growth of CuGaSe₂ solid solutions from nonstoichiometric melts is discussed, especially the most satisfactory Bridgman growth from the Cu₂Se-CuGaSe₂ join. Subsolidus phase relations are also proposed for the Cu-Ga-Se system, and probable similaritics in all I-III-VI ternary diagrams are suggested.     

Liquid-State Interfacial Reactions of Sn-Zn/Co Couples at 250°C

This study examined the interfacial reactions between liquid Sn-Zn alloys and Co substrates at 250°C with different Zn compositions from 1?wt.% to 9?wt.%. The reaction phases formed at the interface were significantly affected by the Zn content. One irregular reaction phase, γ₂-CoZn₁₃, was observed in the Sn-9?wt.%Zn/Co reaction. Decreasing to 7?wt.% Zn, the interfacial product changed to the γ₁ phase. After a longer reaction time, a new ternary compound with composition Sn-20.2?at.%Zn-31.4?at.%Co, the T phase, was formed between the γ₁ phase and Co substrate. Only one very thin and continuous T phase layer was found, and it was stable at the Sn-4?wt.%Zn/Co interface, even after 120?h reaction. However, the Sn-3?wt.%Zn/Co couples revealed significant microstructural evolution in both the T and CoSn₃ layers. Moreover, the dominant phase became CoSn₃ as the Zn content decreased below 2?wt.%. Based on these interfacial results, a predicted Sn-Zn-Co phase diagram (less than 30?at.% Co) at 250°C is proposed. The corresponding reaction paths of these couples are illustrated on the phase diagram.     

Phase distribution and phase analysis in Cu6Sn5, Ni3Sn4, and the Sn-rich corner in the ternary Sn-Cu-Ni isotherm at 240°C

Metallurgical reactions between solders and under bump metallization (UBM) are key issues for the solder joint reliability in microelectronic packaging. A phase diagram consisting of solders and UBM materials are required to further understand the interfacial reactions and related phase transformation. In this study, series of ternary Sn-Cu-Ni alloys were designed, fabricated, and heat-treated at 240°C. Equilibrium phases of Sn, Ni₃Sn₄, and Cu₆Sn₅ were identified by XRD, and microstructure evidence in backscattered electron image (BEI) micrograph. Through detailed EPMA quantitative analysis, three acme compositions of the ternary region in the Sn-Cu-Ni isotherm near the Sn-rich corner were evaluated and determined. Furthermore, x-ray color mapping of tin, copper, and nickel were applied to study the phase distribution of the alloys with the aid of electron microprobe analysis (EPMA). According to the intensities of Sn, Cu, and Ni, collected by x-ray color mapping, special software was employed to map the corresponding concentrations on the Sn-Cu-Ni ternary isotherm. The degree of composition homogeneity and the phase distribution were further evaluated by phase-analysis techniques. Semiquantitative measurements by phase analysis can be extended to evaluate the phase boundaries with a statistical variation under 5% as compared to the quantitative analysis by EPMA. Finally, the isothermal section of the ternary Sn-Cu-Ni system near the Sn-rich corner at 240°C was constructed.