A method to fabricate low temperature adhesively bonded vacuum-sealed insulated polymeric cavities on a silicon substrate is presented. Multi-purpose use of the same polymer (Benzocyclobutene (BCB)) as the cavity structural material and also as an adhesive bonding agent minimizes process complexity, cost, and dielectric charging. Scanning electron microscopy (SEM) based characterization results show excellent planarity of BCB surfaces and high quality bonding which is indicative of better reliability. The method paves the way to fabricate the package and the sensor in the same process run to enable higher level of integration and minimize the cost further. The technique can be used to realize capacitive micromachined ultrasonic transducers (CMUTs), MEMS pressure sensors, and 3D embedded packaging and integration of heterogeneous dies.

提出了一种在硅衬底上制造低温粘合真空密封绝缘聚合物空腔的方法。多用途使用相同的聚合物（苯并环丁烯 (BCB)）作为腔体结构材料以及粘合剂，可最大限度地减少工艺复杂性、成本和介电充电。基于扫描电子显微镜 (SEM) 的表征结果显示 BCB 表面具有出色的平面度和高质量的粘合，这表明了更好的可靠性。该方法为在同一过程中制造封装和传感器铺平了道路，以实现更高水平的集成并进一步降低成本。该技术可用于实现电容式微机械超声换能器 (CMUT)、MEMS 压力传感器以及异质裸片的 3D 嵌入式封装和集成。