Patent ID: 7225675

Claim:
A capacitance type dynamic quantity sensor for detecting a physical dynamic quantity, the capacitance type dynamic quantity sensor comprising: a semiconductor substrate having a weight supported by beams and mounted to undergo displacement due to an applied external dynamic quantity such as acceleration or angular velocity; an upper substrate connected to a part of a first surface of the semiconductor substrate, the upper substrate having a first fixed electrode laminated thereon so as to confront the weight with a minute gap therebetween, the first fixed electrode having a plurality of through-holes extending between opposite main surfaces of the first fixed electrode; and a lower substrate connected to a part of a second surface of the semiconductor substrate, the lower substrate having a second fixed electrode laminated thereon so as to confront the weight with a minute gap therebetween, the second fixed electrode having a plurality of through-holes extending between opposite main surfaces of the second fixed electrode; wherein for each of the first and second fixed electrodes, the through-holes provide the respective first and second fixed electrodes with a comb-shaped structure for preventing the generation of hillocks on surfaces of the first and second fixed electrodes.