单组分加成型导热硅胶的制备及其可靠性研究

Preparation and reliability study of single-component addition-type thermal conductive silica gel

以中低黏度乙烯基硅油、含氢硅油搭配微米氧化铝导热粉体为原料,制备了两款单组分加成型导热硅胶(UB-5705和UB-5707)。通过红外光谱仪分析明确了所得产物,进一步利用差示扫描量热仪、热重分析仪及导热系数测试仪进行性能表征,并进行高温高湿、冷热循环和高温老化可靠性研究。研究结果表明:(1)导热硅胶合成效果良好,符合试验预期,热裂解温度(T_(d))大于250℃,导热系数大于1.90 W/(m·K),热阻低于10.184℃·cm^(2)/W,剪切强度达5.00 MPa以上;(2)相比之下,UB-5705具有更优异的韧性,而UB-5707则具有更高的导热系数;(3)在分别经过1 000 h高温高湿、冷热循环和高温老化后,两款导热硅胶仍能保持较高的导热系数与机械性能,导热系数>1.80 W/(m·K),剪切/拉伸强度>4.0 MPa,断裂伸长率>20%,综合性能满足芯片与散热器组装可靠性要求。

Two kinds of single-component addition-type thermal conductive silica gel(UB−5705 and UB-5707)were prepared by using low to medium viscosity vinyl silicone oil,hydrogen containing silicone oil combined with micron alumina thermal conductive powder as raw materials.The obtained products were clarified by infrared spectrometer analysis,and further characterized by differential scanning calorimeter,thermogravimetric analyzer and thermal conductivity tester.High temperature and high humidity,hot and cold cycling,and high temperature aging reliability studies were also carried out.The research results showed that,(1)The synthesis of thermal conductive silica gel was effective and met the test expectations.The thermal cracking temperature(T_(d))was greater than 250℃,the thermal conductivity coefficient was greater than 1.90 W(/m·K),the thermal resistance was lower than 10.184℃·cm^(2)/W,and the shear strength was more than 5.00 MPa.(2)In contrast,UB-5705 had superior toughness,while UB-5707 had a higher thermal conductivity.(3)After 1000 h of high temperature and high humidity,cold and hot cycling and high temperature aging,respectively,two kinds of thermal conductive silica gel still maintained high thermal conductivity and mechanical properties,with thermal conductivity>1.80 W(/m·K),shear/tensile strength>4.0 MPa,the elongation at break>20%.The comprehensive performance met the requirements for reliability of chip and radiator assembly.