Deep silicon etching technology and applications: a review

Abstract Deep silicon microstructures are pivotal in advancing modern device technologies, enabling critical components such as 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, selectivity and scallop size are additional critical factors. Advanced simulation tools play an essential role in optimizing etching processes and predicting outcomes, enhancing efficiency and accuracy. As technological demands evolve, deep silicon microstructures will remain integral to driving innovation in semiconductor and microdevice fabrication.