低温共烧陶瓷基板的薄膜金属化

就低温共烧陶瓷(LTCC)基板实用化过程中遇到的问题,研究了LTCC基板的薄膜金属化技术;经复合膜系Ti/Ni/Au薄膜金属化的LTCC基板可满足各项技术指标要求,通过考核证明了用此方法制得的基板可靠性高,完全满足使用要求。     

薄膜金属化LTCC基板的薄膜阻碍层对共晶焊的影响

讨论了LTCC工在板薄膜金属化技术中,有效阻碍层的选择对基板共晶焊的影响。实验结果表明,Ti/Ni是一种高可靠性的阻碍层,而且Ti/Ni/Au也是一种较理想的LTCC基板薄膜金属化结构。     

应用于MCM-C/D的减薄抛光工艺

混合型多芯片组件(MCM-C/D)研制技术具有共烧陶瓷技术高密度多层互连集成和薄膜电路高精度和高可靠性等优点,是目前先进实用的混合集成技术.共烧多层基板的总厚度差(TTV)和表面粗糙度是影响共烧多层基板在多芯片组件(MCM)中应用的关键因素.选取低温共烧陶瓷基板,研究了减薄抛光工艺对基板的作用机理,结合实际加工要求选择...     

LTCC基板通孔金属化研究

低温共烧多层陶瓷（ＬＴＣＣ）基板是微电子先进产品ＭＣＭ的重要组成部分。这种基板的通孔金属化是制作成功基板的关键。本文重点分析了形成稳定金属化通孔导体的固有应力和热应力产生的原因,以及如何采取对策来解决。     

MCM多层共烧陶瓷基板技术的研究进展

本文介绍了MCM中的高温共烧陶瓷与低温共烧陶瓷基板技术,以及共烧陶瓷基板技术的研究进展情况。讨论了多层共烧陶瓷基板的关键工艺,比较了HTCC和LTCC的工艺。并对多层共烧陶瓷基板的发展进行了展望。     

高温共烧陶瓷外壳金属化层粘附强度测试方法及其优化

陶瓷外壳、基板、绝缘子等的表面金属化层的粘附强度测试方法有多个标准,且这些标准并不等同,如何正确使用标准并没有明确规定或说明.分析了高温共烧陶瓷外壳金属化层在典型应用情况下的作用,及其与测试方法的关系,提出了高温共烧陶瓷外壳金属化层测试方法、测试注意事项,并做了验证试验,优化的测试方法可更准确地对陶瓷上金属化层粘附强度...     

多层共烧氮化铝陶瓷金属化工艺研究

氮化铝陶瓷因其热导率高、绝缘性好以及无毒害等特点在许多领域有着广泛的应用。多层共烧氮化铝陶瓷是采用厚膜印厣j的方式将多层的电路金属化做入氮化铝基板并在特定气氛中高温烧结的一种高性能陶瓷。金属化是多层共烧氮化铝陶瓷的一个关键工艺,文章主要介绍了对金属化工艺的研究。重点研究了其中的印刷工艺、叠片层压工艺和烧结工艺。通过对印刷和烧结参数的研究,使得生产陶瓷的热导率大于170W（m·K）^-1,金属化的方阻小于18mΩ／□,金属化的抗拉力大于1．8N（1mm^2焊接面积）,能满足大功率LED封装、大功率功率管封装的性能要求,已经在多种陶瓷外壳和基板中应用。     

低温共烧多层陶瓷基板实用化技术研究

在第五代电子组装技术中,低温共烧陶瓷多层基板(LTCC)由于具有高密度布线、高信号传输速度、低损耗和高可靠性,在国内外受到极大重视。自八十年代以来,日、美很多公司做了大量研究工作,开发出这种高技术电路基板,并试制出多芯片组件(MCM),在先进的航天、航空电子设备和复杂的通信机、计算机中得到应用。目前,我国已基本形成一条低温共烧多层陶瓷基板研制线。本文根据电子部43所的研究成果和现有工艺装备,介绍低温共烧多层陶瓷基板的应用情况。     

低烧基板的流延料浆配制及流延工艺研究

陶瓷材料的成膜技术是制造低温共烧多层陶瓷基板的关键技术之一，本文介绍了低温共烧（８００－９００℃），低介电常数（ε〈５）多层陶瓷基板中，流延料浆的配制及最佳流延工艺参数的研究。     

用于半导体激光器热沉的金刚石膜/Ti/Ni/Au金属化体系的研究

提出了一种用于半导体激光器热沉的金刚石膜/ Ti/ Ni/ Au金属化体系.采用金属化前期预处理、电子束蒸镀技术和后续低温真空热处理,金属层和金刚石膜之间获得了良好的结合强度.AES分析表明Ti/ Ni/ Au金刚石膜金属化体系中,Ni层起到了良好的阻挡效果;XRD显示预处理过的金刚石膜,镀膜后经过6 73K,2 h低温真空热处理,Ti/金刚石膜界面形成Ti O和Ti C;RBS分析进一步证实该金属化体系在6 73K,1h真空加热条件下具有良好的热稳定性.采用完全相同的半导体激光器结构,金刚石膜热沉的热阻仅为氮化铝热沉的4 0 % .     

Silicon carbide pinch rectifiers using a dual-metal Ti-Ni/sub 2/Si Schottky barrier

The electrical characterization of dual-metal-planar Schottky diodes on silicon carbide is reported. The devices were fabricated on both 6H- and 4H-SiC by using titanium (Ti) and nickel silicide (Ni/sub 2/Si) as Schottky metals. These rectifiers yielded the same forward voltage drop as the Ti diodes and leakage current densities comparable to those of the Ni/sub 2/Si diodes. The reduction of the reverse leakage current density, with respect to that of the Ti diodes, was about three orders of magnitude in 6H and about a factor of 30 in 4H-SiC. All that results in a consistent reduction of the device power dissipation. Electrical characterization of the devices at different temperatures provided insight into the carrier transport mechanism. In particular, the electrical behavior of the system was explained by an "inhomogeneous" Schottky barrier model, in which the low Ti barrier determines the current flow under forward bias, whereas the high Ni/sub 2/Si barrier dominates the reverse bias conduction by the pinchoff of the low barrier Ti regions.     

High performance of high-voltage 4H-SiC Schottky barrier diodes

High performance of high-voltage rectifiers could be realized utilizing 4H-SiC Schottky barrier diodes. A typical specific on-resistance (R_on) of these devices was 1.4×10³ Ω cm³ at 24°C (room temperature) with breakdown voltages as high as 800 V. These devices based on 4H-SiC had R _on's lower than 6H-SiC based high-power rectifiers with the same breakdown voltage. As for Schottky contact metals, Au, Ni, and Ti were employed in this study. The barrier heights of these metals for 4H-SiC were determined by the analysis of current-voltage characteristics, and the reduction of power loss could be achieved by controlling the barrier heights     

Dual metal SiC Schottky rectifiers with low power dissipation

Nickel and titanium are the most commonly used metals for Schottky barrier diodes on silicon carbide (SiC). Ti has a low Schottky barrier height (i.e. 0.8 eV on 6H-SiC), whilst Ni has a higher barrier (i.e. 1.25 eV). Therefore, the first metal allows to achieve a low forward voltage drop V_F but leads to a high leakage current. On the other hand, the second one presents the advantage of a lower reverse leakage current but has also a high value of V_F. In this work, dual-metal-planar (DMP) Schottky diodes on silicon carbide are reported. The rectifying barrier was formed by using an array of micrometric Ti and Ni₂Si (nickel silicide) stripes. This low/high Schottky barrier allowed to combine the advantages of the two metals, i.e. to fabricate diodes with a forward voltage drop close to that of a Ti diode and with a level of reverse current comparable to that of a Ni₂Si diode. Under the application point of view, using this kind of barrier can lead to a reduction of the device power dissipation and an increase of the maximum operating temperature.     

Schottky barrier heights of n-type and p-type Al0.48In0.52As

The authors report electrical measurements on four different metal contacts which formed Schottky barriers to lightly doped complementary n- and p-type Al_0.48In_0.52As epitaxial material grown by molecular beam epitaxy on semi-insulating InP substrates. The Schottky contact metals studied were Au, Al, Pt, and tri-layer Ti/Pt/Au. The Schottky barrier heights varied from 0.560 eV for Al on n-type AlInAs to 0.905 eV for Al on p-type AlInAs, with intermediate values for the other metals studied. The sum of n- and p-type Schottky barrier heights for each metal contact ranged from 1.440 to 1.465 eV, in good agreement with the accepted Al_0.48In_0.52As bandgap value of 1.45 eV     

缓冲层对铜催化生长碳管形貌和性能的影响

碳纳米管的生长通常使用Fe,Co,Ni作为催化剂,除此以外的一些过渡元素也能催化裂解生长碳管。其中用铜制备的碳管阈值电场低、发射电流密度大、发射均匀性好等等良好的场发射特性。铜与硅、或金属之间具有很强的的扩散特性,而碳管应用于场发射显示器必然使用玻璃、硅片作为衬底,所以需要一层缓冲层阻挡催化剂铜扩散入衬底。本文使用磁控溅射制备铜薄膜作为催化剂,化学气相沉积方法裂解乙炔生长碳管薄膜形成场发射阴极。并试验W,Ni,Cr和Ti作为铜薄膜的缓冲层,结果表明不同的金属阻挡特性不同,生长后碳管的形貌和特性都有差异。结果表明Ti和W能很好地阻挡铜的扩散,从而使铜催化裂解出附着性好、分布均匀、密度适中、场发射特性良好的碳管薄膜。对于Ni和Cr金属,由于生长的碳管与衬底结合差或者场发射能力差而不适合作铜的缓冲层。     

Control of threshold voltage of AlGaAs/GaAs 2DEG FET's through heat treatment

Threshold voltage controls of Ni/Ti/Au gate and Ti/Au gate 2DEG AlGaAs/GaAs FET's through only heat treatment are investigated. Ni/Ti/Au gate FET's vary over quite a wide range from a depletion mode to an enhancement mode without degradation of FET characteristics after heat treatment at 300°C. The same experiment is made for Ti/Au gate FET's, but the threshold voltage change is negligibly small. It is confirmed that Ni/Ti/Au can be used as the gate metal for E-FET and Ti/Au as the gate metal for D-FET under simultaneous heat treatment. In addition, a mechanism for penetrating the barrier metal into the underlying layer is discussed.     

CBS系LTCC材料组分对其性能的影响及其金属化匹配

研究了组分变化对CaO-B2O3-SiO2(CBS)系多元微晶玻璃微观结构、介电性能及相组成的影响.以CBS系微晶玻璃为基础配制生料带,并借助LTCC技术制备了多层微电路基片.探讨了影响LTCC多层微电路低温共烧金属化匹配的相关因素.结果表明:添加不同形态的SiO2均可有效降低微晶玻璃的相对介电常数εr岛,添加高硅氧玻...