导热绝缘胶粘剂的研究进展及其在金属基板上的应用

文章简单介绍了导热绝缘胶粘剂的导热原理,重点分析了导热绝缘胶粘荆中最主要的两类组分--高分子树脂和导热填料的影响及其最新研究进展,概述了该类胶粘剂在金属基板上的应用情况,并对导热绝缘胶粘剂的发展前景进行了展望.     

导热绝缘胶

随着大规模集成电路和微封装技术的发展 ,电路中元器件的组装密度越来越高 ,体积不断缩小 ,元器件的散热将成为一个突出的问题。它将直接影响到使用它们的各种高精密设备的寿命和可靠性。在航空管制中的电子工程设备中 ,作为电源采用大功率晶体管 ,晶体管产生的热量能否及时地散发 ,这对晶体管以致整个设备的性能和寿命都有很重要的影响。资料报导 :当结点温度在 30 0℃时 ,功率管只能用半个月。当结点温度降至 2 0 0℃时 ,寿命可延长到一年 ,当结点温度为 15 0℃时寿命为 10年。由此可知 ,对功率管采用有效的散热措施 ,是一个实际而重要的…     

DBC绝缘导热基板的研制

介绍ＤＢＣ绝缘导热基板的键合机理，重点分析了Ａｌ２Ｏ３－ＤＢＣ基板的制造工艺以及对键合质量有显著影响的若干因素，并给出解决方案。     

绝缘导热浆料制备和性能

以低熔玻璃粉、金刚石粉及有机载体制备成浆料,丝网印刷在硬铝LY12基材上,烧结后制成导热绝缘层。分析了浆料中的金刚石粉含量对绝缘导热涂层导热参数和与基片附着力的影响,测试分析了浆料的流变性和触变性。结果表明,绝缘导热浆料的最佳配方为:w(有机载体)为18%;w(金刚石粉)为30%;w(低熔玻璃粉)为52%。静止时浆料中形成弱的絮凝,是剪切变稀体,有一定触变性,具有较好的丝网印刷适性。所制备绝缘涂层的热导率最高可达2.47W/(m·K)。     

导热绝缘胶的研制和应用方法

讨论了导热系数ｋ与材料本身相联系的因素,以树脂、固化剂和导热绝缘填料的选择组合处理上进行了试验,取得了性能优异的导热绝缘的配方,结合具体的器件与散热构件的组合进行了讨论,取得了良好的散热效果,解决了一些问题。     

高导热挠性金属基板

为了满足电子产品，特别是数码家电小型、轻量化的迫切需要，挠性基板成为必不可少的基板，其使用的范围也越来越广。挠性基板用树脂有聚脂、聚酰亚胺树脂等。其中的聚酰亚胺类挠性基板在耐湿方面还存在许多问题，但其耐热性非常好，机械强度高，被用于手机的活动关节部分。     

高导热多层陶瓷布线基板制造新技术

一般的多层陶瓷基板材料主要是Al2O3。由于Al2O3的导热率低，不适应电子产品小型化、电路高密度化的要求。迫切需要导热率高，散热性能良好的绝缘基板。     

高导热环氧模塑料的制备

介绍了导热系数大于3 W/(m·K)高导热环氧模塑料的制备。以低黏度多芳香环（MAR）环氧树脂和MAR酚醛树脂为基体,以偶联剂处理的球形氧化铝做导热填料,磷类做催化剂,经高速混合机混合、双螺杆挤出机挤出,合成高导热环氧模塑料。并研究了不同偶联剂类型对弯曲强度的影响。通过改变填充量至93%,导热系数最高可达5.6 W/(m·K),且有较好的弯曲性能和流动性能。     

延长高能LED产品使用寿命的绝缘金属基板简介

发光二极管在产生可见光的同时也产生大量的热量。如果使用不当,这些热量会导致电子产品过早地损坏。绝缘金属基板可以解决该问题,同时延长这些产品的使用寿命。     

高导热挠性铝基覆铜板用环氧胶粘剂的研究

采用高导热填料球形氧化铝填充环氧胶粘剂,并添加了适量离子捕捉剂有效地控制有害离子的离子迁移,利用该胶粘剂粘接铝箔和铜箔制备成挠性铝基覆铜板。文章中探讨了环氧胶粘剂的热固化温度和时间、球形氧化铝含量对胶膜热导率的影响,通过显微镜测试了导热填料在胶粘剂中的分散均匀性,最后确定最优配方制备出一种综合性能优异的挠性铝基覆铜板。     

导热绝缘层的韧性及附着力影响因素分析

铝基覆铜板作为电子元器件的载体,以其优异的散热性能,广泛应用于LED、汽车、电视、电源等领域。但由于铝基覆铜板的导热绝缘层附着力差,且导热绝缘层本身韧性低,机械加工时容易出现导热绝缘层崩裂、分层的现象,这是铝基覆铜板开发及制作过程中面临的最大难题之一。本文采用柱轴弯曲试验来评估导热绝缘层的韧性及附着力,并分析了影响铝基覆铜板导热绝缘层韧性及附着力的因素,从试验条件、铝板表面处理方式、导热绝缘层厚度、导热绝缘层配方等方面进行对比,评估不同因素对韧性及附着力的影响情况。     

高导热铝基板用导热绝缘胶的制备

以环氧树脂为基体树脂,氧化铝、氮化硼、氮化硅和二氧化硅混杂粒子为导热填料,制备了一种新型高导热铝基板用导热绝缘胶粘剂。研究了填料种类与用量及硅烷偶联剂对胶粘剂热导率、体积电阻率、介电常数等性能的影响。对于此导热绝缘胶,随着混合填料填充量的增加,导热率呈型上升趋势;混合填料用量为60 wt%时,热导率达到3.81 W/(m.K),是纯环氧树脂胶的10倍以上。     

基于高亮度LED散热基板导热系数的检测方法

导热系数在化工、建筑、科研生产中有着广泛的应用。目前国内外关于导热系数的检测方法很多,相关的标准也不少。检测样本不同,对检测方法的适用领域、测量范围和精度的要求也不同。在检测时,选择合适的检测方法至关重要。通过对比分析国内外各种导热系数的检测方法,引入一种适合印制电路板行业高亮度LED散热基板导热系数的新检测方法。通过试验验证,确定其在高亮度LED散热基板的导热系数检测方面的适用性。     

High temperature reliability of electrically conductive adhesive attached temperature sensors on flexible polyimide substrates

The attachment and packaging of temperature sensors may be challenging due to their structure and materials. Sensing requires a structure which is open to the environment and the materials often differ from those used in silicon-based electronics. Thus, traditional attachment techniques and materials such as soldering may be inappropriate. Polymer-based electrically conductive adhesives (ECA) are an alternative. The operating environment of a sensor may, however, be very demanding. Very little research data is available on the use of ECAs in challenging conditions, thus restricting their use in many applications. This study tested the behaviour of temperature sensors attached with ECAs onto flexible polyimide (PI) substrates in thermal storage at 200 °C. More than 1000 h of testing without failures were conducted on the ECA sensor structures. Good high temperature reliability therefore seems to be possible with ECAs. However, the PI substrate was observed to be critical to reliability. An adhesive layer used in the PI substrate reacted at the test temperature and severe oxidation of the copper pads and reaction between the materials consequently destroyed the interconnection and caused failures.     

高频混压多层板散热性能的局限与改善

印制电路板的散热效果直接影响高频多功能电子产品的可靠性。基于混压高频子板的多层印制电路板,其散热性能受到设计、制造材料与工艺的限制。本文简述了大功率元器件引发高频混压多层板的热问题,探讨了高频混压多层板散热方法及其局限,提出改善高频混压多层板散热性能的有效方法。     

导（散）热印制板

概括地评论了散（导）热PCB 的发展的原因和环境,PCB的高密度化和信号传输的高频化是散（导）热PCB发展的两大主要原因,散（导）热PCB主要是通过三种方法（金属芯板、金属基板和导热性CCL）来实现。     

Preparation of conductive HfN by post rapid thermal annealing-assisted MOCVD and its application to metal gate electrode

Conductive hafnium nitride (HfN) with negligible carbon impurity (<0.1 at.%) was chemically synthesized for the first time by post-rapid thermal annealing (PRTA)-assisted metal organic chemical vapor deposition (MOCVD) method. The thermodynamic instability of N-rich hafnium nitride (Hf₃N₄) phase, which is considered to be the dominant phase in CVD deposition of hafnium nitride, was utilized for pure and metallic HfN synthesis. By integrating the PRTA-HfN film into MOS capacitor, the electrical properties of the PRTA-HfN film as metal gate electrode were studied. Well behaved electrical characteristics such as about 4.9 eV of effective work function, low leakage current and large reduction in SiO₂ equivalent oxide thickness (EOT), which was attributed to the combination of physical thinning of SiO₂ and formation of high-κ interfacial layer, suggest the potential capability of PRTA-assisted MOCVD in chemically synthesizing HfN metal gate electrode for pMOS devices application.     

Study on thermal performance of high power LED employing aluminum filled epoxy composite as thermal interface material

This paper elucidates the thermal behavior of an LED employing metal filled polymer matrix as thermal interface material (TIM) for an enhanced heat dissipation characteristic. Highly thermal conductive aluminum (Al) particles were incorporated in bisphenol A diglycidylether (DGEBA) epoxy matrix to study the effect of filler to polymer ratio on the thermal performance of high power LEDs. The curing behavior of DGEBA was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The dispersion nature of the Al fillers in polymer matrix was verified with Field Emission Scanning Electron Microscope (FESEM). The thermal performance of synthesized Al filled polymer composite as TIM was tested with an LED employing thermal transient measurement technique. Comparing the filler to polymer ratio, the rise in junction temperature for 60 wt% Al filled composite was higher by 11.1 °C than 50 wt% Al filled composite at cured state. Observed also from the structure function analysis that the total thermal resistance was 10.96 K/W higher for 60 wt% Al filled composite compared to 50 wt% Al filled composite. On the other hand, a significant rise of 9.5 °C in the junction temperature between cured and uncured samples of 50 wt% Al filled polymer TIM was observed and hence the importance of curing process of metal filled polymer composite for effective heat dissipation is discussed extensively in this work.