D-Baw Uniformity Improvement by Resonator Thickness Compensation

This study primarily achieves its goal through a special process flow method, which allows for altering the thickness of one side’s metal electrode, while simultaneously making a non-linear compensatory change in the thickness of the opposing metal electrode or the passivation layer of the electrode. By doing so, this innovation ensures that the performance of the resonator remains unaffected and, at the same time, enhances the consistency across the entire wafer without compromising the functionality of the resonators. Since the amount of thickness change introduced by this method is small, it does not affect the performance of the resonator. The advantage of this method lies in the fact that, prior to making thickness variation compensation on the opposing metal electrode or electrode passivation layer, the filter performance in different regions of the wafer can be obtained through RF electrical testing. Based on these results, an accurate thickness change amount can be determined and applied to either the metal electrode or the electrode passivation layer. This change amount is tailored according to the corresponding RF test results for each specific wafer region, with the aim of enhancing the uniformity across the entire wafer. Ultimately, this approach serves to increase the yield of the entire wafer.