MEMS fabrication is a systematic manufacturing technology used to create micro-electro-mechanical devices that combine mechanical structures, electronic functions and signal interaction. It is widely used in sensors, actuators, RF components, microfluidic devices and biomedical systems.
Lithography is used to define microstructure patterns on the wafer surface. The pattern is transferred to photoresist and then used as a mask for etching, deposition or implantation. Lithography accuracy directly affects device dimensions and alignment.
Etching removes selected materials to form cavities, trenches, membranes, beams or channels. Wet etching is cost-effective and material-selective, while dry etching such as RIE or DRIE provides anisotropic profiles and high-aspect-ratio structures.
Thin-film deposition forms functional layers, electrodes, structural layers and insulation layers. PVD, CVD, PECVD and ALD may be selected according to material, film quality and temperature requirements.
Wafer bonding and release processes are used to build cavities, seal structures and free movable parts. Anodic bonding, direct bonding, eutectic bonding and sacrificial-layer release are common routes, depending on material combination and device design.
MEMS packaging must protect delicate structures while allowing mechanical, pressure, acoustic, optical or fluidic interaction with the environment. Hermeticity, stress isolation, thermal stability and media compatibility are important considerations.
Testing includes electrical, mechanical, environmental and reliability evaluation. Parameters such as sensitivity, response speed, power consumption, vibration resistance and long-term stability must be verified before application.
Because MEMS devices vary widely in structure and function, process customization is often required. Successful MEMS manufacturing depends on coordinated design, process development, material selection, packaging and testing.
