Experimental Study On PEO-LiClO₄/Al Ultrasonic Assisted Anodic Bonding Process

Anodic bonding is one of the key technologies in MEMS packaging.With the continuous development of MEMS,the quality of packaging has become one of the bottlenecks restricting the development of MEMS.The development of traditional materials can no longer adapt to their applications,so the development of new materials and the optimization of bonding processes have become important research hotspots.In this paper,the ultrasonic field was first introduced into the anode bonding high-voltage electric field.For the composite anode bonding system and the demand for the bonding process,an ultrasonic auxiliary anode bonding test device was built independently.In order to meet the high-voltage electric field requirements of the anodic bonding process,the control system,etc.,have designed ultrasonic transducers,ultrasonic amplitude rods,and ultrasonic welding heads.Using polyoxyethylene（PEO）as the base alkali metal lithium salt（LiClO₄）as the conductive ion donor,using high-energy ball milling and tableting technology,PEO-based solid polymer electrolyte material PEO-LiClO₄ was prepared,and the performance analysis of the material（XRD,infrared spectroscopy,DSC curve,AC impedance）,the performance test shows that the introduction of Li salt can reduce the crystallinity of the polymer,and the final use of PEO and LiClO4 mass ratio of 10:1,ball material ratio 7:1,grinding ball diameter 2/3/4（1:1:1）mm,rotation speed 250r/min,ball milling time 8h,the polymer solid electrolyte needed in this paper was prepared.The study found that ultrasonic amplitude and bonding voltage are the two most important process parameters in ultrasonic-assisted anodic bonding.When the bonding voltage does not change,as the ultrasonic amplitude increases,the bonding current peak becomes larger,and the bonding rate also increases When the amplitude of the ultrasonic wave is constant,as the voltage becomes larger,the peak value of the bonding current also becomes larger,and the bonding rate also becomes larger.Ultrasonic treatment is used to perform anodic bonding rather than ultrasonic treatment,the maximum current of bonding becomes larger,the bonding transition layer is significantly thicker,and the bonding quality is improved.