Assembly Process Improvement For MEMS Microphone IC Chip

MEMS Microphone is newly developed technology , it is the combination of multi -kind technology:MEMS technology and Standard IC technology.MEMS Microphone can use standard semiconductor assembly process flow and technology, it is widely used in consumable products or portable product:mobile phone,digital camera,and laptop due to it’s shrink size and capable to be mounted on motherboard by SMT technology,SMT application will much helpful for productivity improvement and cost down.Microphone market future is MEMS microphone。MEMS Microphone consist two chips:MEMS chip and IC chip.Two Key topic will be studied for MEMS microphone IC chip assembly process, the first one is IC chip encapsulation process optimization improvement and the second one is IC chip wire bonding process optimization. As for encapsulation,we will study two kinds of dispensing method:needle dispensing method and Jetting on the fly technology.Jetting on the fly technology show much advantage considering the yield and cost effectiveness.and it did help the yield improvement for encapsulation process.the next step for Jetting dispensing is to analyze each failure mode,also include cause and effective analysis, then to optimize the critical parameter:dot size,dispensing time,dispensing gap ,dispensing pressure and nozzle size to reduce such failure mode.meanwhile we also performed some basic analysis for epoxy characteristic to try to find one that is more suitable for IC encapsulation process.As for wire bonding process optimization and improvement,we will perform some analysis for pad peeling failure,find the cause by using different analysis equipment:EDX,SEM and cross section method.Finally the solution is ready for wire bonding pad peeling reduction and get quite progressive result.