Deep Silicon Etching Technology and Applications: A Review

Deep silicon microstructures play a critical role in modern device technologies, including trench gates, p-n junctions, deep trench isolation, through-silicon vias, and dicing. The fabrication of these structures is primarily achieved through plasma etching and electrochemistry-enhanced wet etching. Key performance metrics, such as aspect ratio, profile accuracy, etch rate, and etch rate uniformity, are essential for evaluating the quality of the etching process. Challenges such as etch rate non-uniformity, which manifests as microtrenching, loading effects, aspect ratio-dependent etching, and tilt effects, require careful consideration. In plasma etching, additional criteria such as selectivity and scallop size are also significant. Furthermore, simulation methods have become invaluable in optimizing etching processes and predicting outcomes. As technology advances, deep silicon microstructures will continue to be indispensable in driving innovation in device fabrication.