关键词: 压力传感器, 四甲基氢氧化铵, 硅槽结构, 湿法刻蚀

Abstract: The critical stress-sensitive thin film etching in pressure sensors is investigated. Experiments are conducted using tetramethylammonium hydroxide (TMAH) solution to etch silicon trenches at different temperature conditions. Characterization tests of silicon trench etching are performed using a step profiler and a scanning electron microscope (SEM) to analyze the effects of temperature on etching rate, surface morphology, and uniformity. At an etching temperature of 80 °C, the film thickness uniformity for high-planarity silicon deep trench structure reaches 0.038%, with a yield rate of 92.67%.

Key words: pressure sensor, TMAH, silicon trench structure, wet etching