LCP柔性基板的薄膜电阻制作技术

针对液晶聚合物(LCP)柔性基板高频电子封装应用需求,采用一种薄膜溅射工艺直接在LCP柔性基板上制作TaN薄膜电阻,研究不同等离子体预处理方式对LCP表面形貌和LCP表面薄膜金属膜层附着强度的影响,进一步研究溅射气压和氮气体积分数等参数对电阻性能的影响,考察LCP柔性基板上的TaN薄膜电阻精度及电阻温度系数(TCR),并制备出50Ω的薄膜电阻。结果表明:当射频功率为300 W的氧等离子体预处理600 s时,LCP表面的面粗糙度低,LCP基板表面薄膜金属膜层附着强度高,其值>5.0 N/mm²;当溅射功率为400 W、氮气体积分数为3%、溅射气压为0.2 Pa时,制备的TaN薄膜电阻的阻值精度高,阻值精度≤±4%,TCR电阻稳定性能好。

Fabrication Technology of the Thin Film Resistor on LCP Flexible Substrate

In order to meet the application requirement of the liquid crystal polymer(LCP)flexible substrate for high frequency electronic packaging,thin film sputtering process was adopted to fabricate the TaN thin film resistors on the LCP flexible substrate directly.The effects of different plasma pretreatment methods on the surface morphology of the LCP and the adhesion strength of the metal film on the LCP surface were studied,and the influences of the sputtering pressure and nitrogen volume fraction on the resistance performance were further studied.The resistance accuracy and temperature coefficient of resistance(TCR)of the TaN thin film on the LCP flexible substrate were investigated,and a 50Ωthin film resistor was prepared.The results show that when the oxygen plasma with 300 W radio-frequency power is used to pretreat for600 s,the surface roughness of the LCP surface is low,the strength of the metal film on the LCP substrate is high and the adhension strength is more than5.0 N/mm².When the sputtering power is 400 W,the nitrogen volume fraction is 3%and the sputtering pressure is 0.2 Pa,the resistance accuracy of the prepared TaN thin film is high,the resistance accuracy is no more than±4%,and the resistance stability of the TCR is good.