Latest Advance in Fabrication Technologies of MEMS-Type Capacitance Diaphragm Gauge

The latest progress in fabrication technologies of MEMS-type capacitance diaphragm vacuum gauge, a miniaturized gauge fabricated by Micro Electro Mechanical System (MEMS) technology, was tentatively discussed.The discussions with specific examples centered on the major problems and solutions: i) the methods to widen the measurement range, including the multilayered structure, electrostatic servo mode, touch mode and etc.; ii) the ways to improve the output linearity, such as the integration of CMOS circuits, structure modification of diaphragm gauge and stress compensation with proper composite coatings; and iii) the strengths and weaknesses of packaging/sealing techniques, including the conductive adhesive bonding, glass-silicon bonding, silicon-silicon bonding, metalmetal bonding and silicon-on-nothing (SON) bonding. The development trends of MEMS-type capacitance diaphragm gauge were also briefly discussed in a thought provoking way.