Sintering Strength of Pressureless Nano-Silver Paste Between Molybdenum-Copper Carrier and Aluminum Alloy Shell at Low Temperature
The sintering temperature of nano-silver paste is generally 250 ℃ or even higher.While in the power module assembly process,the sintering temperature of the nano-silver paste should not exceed 217 ℃ during the multi-temperature gradient assembly process.The 800HT2V nano-silver paste was used to sinter molybdenum-copper carrier and aluminum alloy shell.The micro-morphologies of nano-silver paste assembled at different sintering temperatures were observed.The changes of shear strength and thermal conductivity after assembly were tested,and the temperature shock test was carried out.The test results show that the shear strength of the sintered sample meets the requirements of the standard.With the increase of sintering temperature,the thermal conductivity and shear strength of the nano-silver paste are obviously improved,and the sintering body is fully sintered and formed at the highest tempera-ture of 200℃.The shear strength of the sintered sample decreases to a certain extent after the tempera-ture shock test.The shear strengths of the sintered samples at the highest sintering temperature of 150 ℃and 175 ℃ decrease by more than 40％,while the strength of the sintered sample at the highest sintering temperature of 200 ℃ only decreases by 21.2％.For long-term reliability of power modules,the nano-silver paste is recommended to be sintered at the highest temperature of 200 ℃.
万方数据
维普
