Study of Thermal Efficiency Optimization In a Twin-Bubble MEMS Micro-Injector

摘要

The methodology of design optimization to achieve optimal thermal efficiency of a twin bubble MEMS micro-injector is reported. We demonstrated that the SiN layer in-between the heater and the ink has dominant effect in optimizing the thermal efficiency of this twin bubble MEMS micro-injector structure. A SiN layer in-between heater and ink of 0.72 μm in thickness is proven for good thermal efficiency as well as good printing quality. In this work, Asai's model has also been demonstrated to be appropriate for back shooting MEMS micro-injector structure design optimization. From the experiment, we can see that SiN layer at about 0.72 μm in thickness demonstrates better characteristics on thermal efficiency as well as good mechanical strength. By using this simulation tool, the layer thickness effect on bubble nucleation is well illustrated and optimized to achieve heater structure design optimization.