Originally, an AlN/Al multi-layer is used as the Bragg reflector.The poor surface roughness of this Bragg reflector results in a poor SMR frequency response.

• 本研究发现，多层薄膜之表面粗糙度为主导声波谐振响应之关键参数，可藉由材料的选择与调变制程参数来研制平整度佳之布拉格反射器；