导电胶固化状态对器件内部水汽含量的影响  

Influence of Curing State of Conductive Adhesive on Moisture Content in Device

作　　者：侯耀伟 杜勿默 王喆 HOU Yaowei;DU Wumo;WANG Zhe(The 13th Research Institute of CETC,Shijiazhuang 050051,China)

机构地区：[1]中国电子科技集团公司第十三研究所,河北石家庄050051

出　　处：《电子质量》2023年第5期90-94,共5页Electronics Quality

摘　　要：气密性封装器件的芯腔内部如果存在大量的水汽,则会影响器件的可靠性,因此在封装的过程中,要对器件内部的水汽含量进行控制。但是目前的控制措施主要是从封帽环境、原材料等方面入手,对导电胶固化状态对器件内部水汽含量的影响研究得较少。因此,首先,对比了不同固化状态导电胶的固化度和吸水率;然后,对不同固化状态对器件内部水汽含量的影响进行了研究。结果表明,充氮烘箱的装载量会影响导电胶的固化状态。当导电胶在300℃下的固化时间为30 min时,其固化度为100%,吸水率约为0.45%;当在300℃下的固化时间为10 min时,其固化度约为92%,吸水率约为0.94%。导电胶固化不充分时,其在温度循环和高温烘烤中会继续固化,并释放出少量的水汽和大量的二氧化碳。固化不充分的导电胶会在双85试验中吸收水汽,即使器件在封帽前会进行烘烤,吸收的水汽也未能完全排出,导致器件内部水汽含量升高。随着烘烤时间的增加,器件内部水汽含量逐渐地减少,当将烘烤时间延长至13 h时,可有效地去除固化不充分导电胶吸收的水汽,使水汽含量低于1000×10^(-6)。If there is a lot of water vapor in the core cavity of air-tight packaging device,the reliability of the device will be affected.Therefore,in the process of packaging,the water vapor content inside the device should be controlled.However,the current control measures mainly start from the sealing environment,raw materials and other aspects,and the influence of the condective adhesive curing state on the water vapor content in the device is less studied.Therefore,firstly,the curing degree and water absorption of conductive adhesives with different curing states are compared.Then,the influence of different curing states on the water vapor content in the device is studied.The results show that loading capacity of nitrogen-filled oven will affect the curing state of the conductive adhesive.When the curing time of conductive adhesive is 30 min at 300℃,its curing degree is 100%and the water absorption rate is about 0.45%.When the curing time is 10 min at 300℃,its curing degree is about 92%and the water absorption rate is about 0.94%.When the conductive adhesive is not cured sufficiently,it will continue to cure in the temperature cycling and high temperature baking,and release a small amount of moisture and a large amount of carbon dioxide.Insufficiently cured conductive adhesive will absorb moisture in the double 85 test,even though the device will be baked before sealing the cap,the absorbed moisture will not be discharged completely,resulting in an increase of moisture inside the device.With the increase of baking time,the moisture content in the device gradually decreases,when the baking time is extended to 13 h,the moisture absorbed by the insufficient cured conductive adhesive can be effectively removed,so that the moisture is less than 1000×10^(-6).

关 键 词：导电胶 内部水汽含量 封装 吸水率 固化度 

分 类 号：TN305[电子电信—物理电子学]