Electrosatatic capacitive sensor and method for manufacturing the same

摘要

A miniature electrostatic capacitive sensor in which electrical insulation is reliably established between a CV conversion circuit (22) and a sensing unit (21). Also disclosed is a manufacturing method for the above type of capacitive sensor. The capacitive sensor is constructed of a sensing unit (21) having a movable electrode (25) and a stationary electrode (26), and a CV-conversion-circuit-forming portion (32) having a CV conversion circuit (22). The movable electrode (25) is constructed of a first support portion (27), a leaf spring (28) connected to the first support portion (27), and a mass portion (29) movably supported by the leaf spring (28). The stationary electrode (26) is formed of a second support portion (30) and a projecting portion (31) connected to the second support portion (30). The CV-conversion-circuit forming portion (32) and the first and second support portions (27, 30) are made thin. Accordingly, a shallow clearance is formed between the CV-conversion-circuit forming portion (32) and each of the first support portion (27) and the stationary electrode (26). An insulating substance (33A, 33B) can thus be positively deposited in the clearance, thereby forming an electrically insulating portion between the CV conversion circuit (22) and the sensing unit (21).