低温共烧陶瓷等七项目入围信息业重大发明

“低温共烧陶瓷（LTcc）”等七大产业前景良好的技术发明项目日前入选2012年信息产业重大技术发明。工信部日前公示了“2012年（第十二届）信息产业重大技术发明评审结果”,共有7个项目入选。低温共烧陶瓷（LTCC）关键材料、工艺技术、及器件设计是其中之一。该设计由清华大学和顺络电子共同完成。低温共烧陶瓷技术（LTCC）是无源电子元件集成和电子元器件高密度封装的关键技术。该技术的产品应用对象主要有手机、蓝牙终端、     

LTCC材料技术运用与发展前景

低温共烧陶瓷(LTCC)技术是最近几年发展起来令人瞩目的电路封装技术,其质料从简略到复合、从低介电常数到高介电常数的不竭发展,技术的成熟水平、产业化水平及利用普遍水平等角度不竭增添。LTCC技术已经成为无源集成的主流技术,亦是无源元件的领域发展方向和新型电子元器件模块化主要技术之一。为迎合目前的发展趋势,本文论述了LTCC材料、LTCC技术和LTCC器件的应用以及未来市场前景。     

微波毫米波用低介电常数低温共烧陶瓷研究进展

在新一代高速无线通信技术推动下，低温共烧陶瓷技术(LTCC)正处于重大变革时期。采用低介电常数(K)、低损耗、谐振频率温度稳定型LTCC作为高频基板材料，可以满足无线技术高速率、低延时、高可靠的需求，是当前热点研究之一。因此商用基板材料的现状和一些候选材料的研究工作被主要评述，重点对玻璃/陶瓷体系、氧化物助烧体系、氟化物助烧体系、本征低温烧结体系等低K值LTCC材料的组成、结构特征、介电性能、热膨胀系数等具体指标及相应优缺点进行了讨论。同时介绍了一些热门体系的改性工作及其毫米波适用性，最后对未来低K值LTCC材料的发展进行展望。     

低温共烧陶瓷技术前景

介绍了低温共烧陶瓷（LTCC）的概念和特点，总结了LTCC的国内发展现状以及新产品开发进展，最后介绍了LTCC产品的广泛应用。     

陶瓷云科技服务集成平台的研究与实现

针对我国陶瓷行业中小企业偏多,优势科技资源高度集中,资源利用率不高的现状,围绕陶瓷企业技术创新、营销管理和公共科技服务需求,构建陶瓷云科技服务集成平台。文章在分析现有云服务平台及其相关技术研究现状的基础上,给出了陶瓷云科技服务集成平台的总体架构及其关键技术,如基于云平台、统一身份认证的安全交易技术,基于云工作流的服务编排与调度技术,线下服务资源建模技术,基于行业知识的WEB服务组合技术等。在现有平台和技术的研究基础上,研发和部署陶瓷云科技服务集成平台的公共基础构件,实现了陶瓷云科技服务集成平台原型的建设。     

低温共烧陶瓷前景广阔

1 LTCC的概念及特点 所谓低温共烧陶瓷（Low-Temperature Cofired Ceramics,简称LTCC）技术,就是将低温烧结陶瓷粉制成厚度精确而且致密的生瓷带,作为电路基板材料,在生瓷带上利用激光打孔、微孔注浆、精密导体浆料印刷等工艺制出所需要的电路图形,并将多个无源元件埋入其中,然后叠压在一起,在900℃下烧结,制成三维电路网络的无源集成组件,也可制成内置无源元件的三维电路基板,在其表面可以贴装IC和有源器件,制成无源/有源集成的功能模块.     

信息集锦

我国将重点发展的陶瓷品种据悉,在今后若干年我国将重点发展的陶瓷品种主要有：一、艺术陈设类陶瓷高低档次全面发展。这类陶瓷主要有盘、台灯、花盆、小雕塑等观赏和使用结合于一身的品种,发展中国传统、西洋、古典。乡村题材等陶瓷表面图画。二、卫生陶瓷发展中高档品种,改进瓷砖和琉璃瓦釉面装饰和彩绘装饰,以提高档次。三、发展技术陶瓷品种。将现有的工程陶瓷、高温结构陶瓷技术,用于开发生产电子元件和蜂窝陶瓷净化汽车尾气等机件供出口。四、发展旅馆用陶瓷花色品种。士。洗手盆、浴盆、炊具和耐高温烧盘等,使旅馆陶瓷成为重要…     

玻璃／陶瓷体系低温共烧陶瓷的研究进展

低温共烧陶瓷（LTCC）是现代做电子封装中的重要组成部分,因其性能优良而得到了广泛应用。LTCC基板材料可以分为玻璃／陶瓷体系和微晶玻璃体系两大类。本文叙述了玻璃／陶瓷体系低温共烧陶瓷的材料组成、研究现状、存在问题以及未来的发展趋势。     

水基流延法制备掺杂ZnO-TiO_2系微波介质陶瓷及性能研究

利用低温共烧陶瓷(简称LTCC)技术设计制造片式多层微波器件已成为当今的研究热点。ZnO-TiO2系微波介质陶瓷具有介电常数适中、介电损耗低、频率温度系数可调和低温烧结等特点,它是具有开发价值的LTCC微波介质材料。实验结果表明:在ZnO-TiO2系统中加入微量的添加剂MgCO3与ZrO2,构成双元复合取代掺杂系统Zn1-xMgxTi1-xZrxO3,当x值取0.07时,最佳介电性能为:εr为29.4,Qf为4285GHz,τf为-8ppm/℃,且该微波介质陶瓷适合于水基流延成型和低温烧结,为LTCC微波介质陶瓷产业化打下了良好的基础。     

功能奇特的陶瓷

?功能奇特的陶瓷,让手机轻薄短小的“陶瓷”。记得几年前“大哥大”刚问世时又大又长,笨重不方便携带使用。随着科技进步,现在的手机就越来越迷你袖珍化了。那么,到底是何种技术让手机从巨大身型变成如今可以顺手掌握的宠物呢?据有关资料介绍:手机可做这么小,其实正是IC的进步,原因是它把很多的功能、组件整合到IC里面;另外一个技术则指LTCC技术加上电路板的技术。LTCC技术是把很多东西整合在一起,其全名为“低温共烧陶瓷技术”,简单地说,就是一种整合、小型化的技术将各种被动组件整合、缩小到陶瓷电路板上,如果没有它,手机也无法达到…     

Zero Shrinkage of LTCC by Self-Constrained Sintering

Low shrinkage in x and y direction and low tolerances of shrinkage are an indispensable precondition for high-density component configuration. Therefore, zero shrinkage sintering technologies as pressure-assisted sintering and sacrificial tapes have been introduced in the low-temperature co-fired ceramics (LTCC) production by different manufacturers. Disadvantages of these methods are high costs of sintering equipment and an additional process step to remove the sacrificial tapes. In this article, newly developed self-constrained sintering methods are presented. The new technology, HeraLock^®, delivers LTCC modules with a sintering shrinkage in x and y direction of less than 0.2% and with a shrinkage tolerance of ±0.02% without sacrificial layers and external pressure. Each tape is self-constrained by integration of a layer showing no shrinkage in the sintering temperature range of the LTCC. Large area metallization, integration of channels, cavities and passive electronic components are possible without waviness and camber. Self-constrained laminates are an alternative way to produce zero shrinkage LTCC. They consist of tapes sintering at different temperature intervals. Precondition for a successful production of a self-constrained LTCC laminate is the development of well-adapted material and tapes, respectively. This task is very challenging, because sintering range, high-temperature reactivity and thermal expansion coefficient have to be matched and each tape has to fulfill specific functions in the final component, which requires the tailoring of many properties as permittivity, dielectric loss, mechanical strength, and roughness. A self-constrained laminate is introduced in this article. It consists of inner tapes sintering at especially low-temperature range between 650°C and 720°C and outer tapes with an as-fired surface suitable for thin-film processes.     

Effect of Metallization on the Lifetime Prediction of Mechanically Stressed Low-Temperature Co-Fired Ceramics Multilayers

Multilayer ceramics based on Low-Temperature Co-fired Ceramics (LTCC) are gaining increasing interest in the manufacturing of high-integrated devices for microelectronic and sensor applications. In many applications the parts are exposed to mechanical stresses, which is an important issue regarding the reliability of the device. To predict the lifetime of LTCC multilayer devices, and to extend their application range, basic mechanical data of this material are needed. In this paper metallized LTCC multilayers are investigated concerning their flexural strength, crack growth rate, and lifetime prediction. The results show that the electronic layout concerning the location of vias and metallization has a strong influence on the reliability and lifetime prediction of such co-fired LTCC devices. Mass flow sensors for the measurement of injected fuel quantities, which were fabricated on the basis of LTCC and which are exposed to a stress level of 100 MPa, achieve sufficient lifetimes. Therefore, LTCC is an interesting material to fabricate devices, in which LTCC fulfils the requirements of a functional and structural material.     

Elevated temperature impact on performance of Low Temperature Co-fired Ceramic dielectrics

The need for electronics to operate at temperatures of 200°C and above continues to grow. These applications include avionics, aerospace, automotive, downhole drilling, mining, and many others. To satisfy this demand, a significant amount of research and development has been conducted. Despite the efforts, the number of new electronic components designed specifically for high-temperature operation is still relatively limited. In Low Temperature Co-fired Ceramic (LTCC) packages, LTCC materials are generally used as the host media for a number of pre-fabricated semiconductor components. As a result, reliability of the entire LTCC package largely depends on the performance of the least robust component. Ferro A6M-E and Ferro L8 are the two well-established and recognized LTCC dielectrics widely used for mid and high frequency LTCC applications, including several high reliability aerospace and defense applications that require demanding Mil-Spec qualifications. This study is our first attempt to characterize and understand basic high-temperature dielectric properties of these two commercial LTCC materials. The secondary objective is to initiate a dialogue in attempt to establish reliability requirements for LTCC packages dedicated for high-temperature operation.     

Integration of transparent glass window with LTCC technology for μTAS application

The LTCC substrate makes it possible to build various microsystems which integrate not only passive components such as resistors, capacitors and inductors but also 3D structures such as cavities and channels. Nevertheless non-transparency is a main limitation of the LTCC-based microfluidic systems. The goal of this paper is to present technology which allows an optical transparent element to integrate with LTCC co-firing process. A micrototal analysis system (μTAS), which is based on the LTCC–glass technology, enables optical measurements. The study shows that integration of sodium glass material is feasible not only with zero-shrinkage LTCC (HL 2000, HL 800) but also with a standard one (DP 951). A FEA (finite element analysis) is used to calculate stress inside the LTCC–glass structure. A series of LTCC–glass windows with different sizes and shapes is investigated to observe size limitation of the integration method. The example ceramic–glass structures (chambers, mixer) with glass windows are made in order to present the possibilities of this new technology.     

High-resolution patterning on LTCC by transfer of photolithography-based metallic microstructures

The growing applications and constant miniaturization of electronic devices and of low-temperature co-fired ceramics (LTCC) in various fields, such as aviation, telecommunications, automotive, satellite communications, and military, have led to an increase in the demand for LTCC. Such prospects arise due to the continuous scaling down of components and high-density interconnection in electronics packaging. This paper reports a technique for the transfer of high-resolution microstructures from silicon substrates to LTCC. In this method, gold and copper patterns were formed by photolithography, electrodeposition, and residual layer stripping on silicon substrate. Lithography provides the opportunity to create and transfer complex patterns for use in several different applications and electroplating enables the use of pure metal for excellent electrical properties. The developed structures were transferred onto a top layer of LTCC tape using hot embossing. Then, the subsequent layers were stacked, laminated, and sintered. A resolution of 1.5 μm after free sintering and 4.5 μm after pressure-assisted sintering was achieved. This distinctive method can be useful for several applications requiring high-resolution and superior electrical properties.     

Strength reliability of 3D low temperature co-fired multilayer ceramics under biaxial loading

Low temperature co-fired ceramics (LTCCs) are multilayered ceramic based components, which can be used as high precision electronic devices in highly loaded environments. In many applications, LTCC end components are exposed to mechanical stresses, which may yield different types of failure coming from different locations, thus decreasing the mechanical reliability of the device. The aim of this work is to assess the mechanical strength of LTCC parts and investigate the influence of the metal internal structure (supporting the maximum load) on the local fracture response. Strength of different positions (e.g. near vias, metal-pads, ceramic layers) has been measured under biaxial loading and compared with a reference bulk LTCC. The strength results were interpreted in the framework of Weibull theory. Fractographic analyses revealed a significant effect of the first metallisation layer below the tensile surface on the strength reliability of the structure, which should be considered to optimise LTCC designs.     

Fabrication of Low-Temperature Co-Fired Ceramics Micro-Fluidic Devices Using Sacrificial Carbon Layers

Ease of fabrication and design flexibility are two attractive features of low-temperature co-fired ceramics (LTCC) technology for fabrication of complex micro-fluidic devices. Such structures are designed and processed using different shaping methods, the extent and complexity of which depends on the final device specifications (dimensions, and mechanical and functional properties). In this work, we propose a sacrificial layer method based on carbon-black paste, which burns out during the LTCC firing stage. The article will summarize the preparation of the paste, influence of processing conditions on the final dimensions, and demonstrate the mechanically integrated structures obtained using this technique. Some of these are membranes of various diameters (7–12 mm) with a thickness of 40 μm and a variety of internal spacing (15–60 μm), free-hanging thick-film resistor bridges on LTCC for heating micro-volumes. The main methods of the study will be thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and dilatometry in addition to electronic instruments for device characterization.     

Graphical based characterisation and modelling of material gradients in porosified LTCC

The chemical composition of low temperature cofired ceramics (LTCC) allows to locally embed air into sintered substrates by a selective wet chemical etch process. Therefore, LTCC substrate with areas of low permittivity can be created without material combination. The presented graphical method of material component contrast images enables the evaluation of their most important material properties which are their component distribution, their porosification gradient and their residual bearing surface. The graphical method, including focused ion beam and scanning electron microscopy analyses, is applied to different commercially available LTCC types having two porosification states each. Derived mathematical models, which are suitable for finite element method implementation, allow the characterisation of the effective permittivity reduction while keeping a maximum residual surface area for, e.g., metallisation purposes. The shape of the optimum material distribution function features an ‘air pocket’ of small width and a depth being dependent on the application specific operating frequency.     

Fabrication of embedded microfluidic channels in low temperature co-fired ceramic technology using laser machining and progressive lamination

This paper describes the application of laser micromachining techniques for the fabrication of microfluidic channels in low temperature co-fired ceramic, LTCC, technology. It is shown that embedded cavities can be successfully realised by employing a recently proposed progressive lamination process with no additional fugitive material. Various microfluidic structures have been fabricated and X-ray imaging has been used to assess the quality of the embedded channels after firing. The problem of achieving accurate alignment between LTCC layers is addressed such that deeper channels, spanning more than one layer, can be fabricated using a pre-lamination technique. A number of possible applications for the presented microfluidic structures are discussed and an H-filter particle separator in LTCC is demonstrated.     

Tailored and deep porosification of LTCC substrates with phosphoric acid

Low temperature co-fired ceramics (LTCC) as an advanced technology for robust assembly of electronic components, has attracted significant attention in a wide application range such as in wireless communication or automotive radar systems. However, accurate designs of micromachined devices operated at high frequencies require substrates with regions of tailored permittivities. Introduction of controlled porosity into the substrate via wet-chemical etching procedure, is a promising approach for permittivity reduction which can be applied to commercially available LTCC without necessitating to alter their composition or sintering process. In the present study, by selective dissolution of celsian phase a very deep porosification (highest reported so far) could be realized while preserving the surface quality. Also, by a careful selection of the etching parameters, the depth of porosification and hence the permittivity reduction can be delicately tailored. Laser ablation inductively coupled plasma mass spectrometry was used for the investigation of chemical compositions of substrates.