An electrostatic device includes: a fixed portion, a moveable portion, and an elastically-supporting portion that are formed in a same substrate; and a first glass package and a second glass package that are anodically bonded to each other on one and the other of front and back surfaces of the substrate with the fixed portion and the elastically-supporting portion separated from each other, the second glass package forms a sealed space in which the moveable portion is arranged between the first and second glass packages, an electret is formed at least partially in the fixed portion and the moveable portion, and a first electrode connected to the fixed portion and exposed on an outer surface of the second glass package and a second electrode connected to the elastically-supporting portion and exposed on the outer surface of the second glass package are formed in the second glass package.

A microelectromechanical system includes a backplate and a diaphragm. The backplate includes spaced stator elements with voids formed therebetween. The stator element includes a first conductive element. The diaphragm includes a plurality of corrugations facing the voids respectively. Each corrugation includes a groove formed at a surface thereof away from the backplate. The corrugation includes a second conductive element. The diaphragm is moveable with respect to the backplate in response to a pressure exerted thereon to cause the corrugations to be moved into or out of the corresponding voids, thereby changing the capacitance formed between the first and second conductive elements. The corrugations are defined by grooves formed at surfaces away from the backplate, which facilitate to control the compliance of the diaphragm and reduce stiffness of the diaphragm. The corrugation can be formed with lower aspect ratios, which allows it to be formed using standard front side processes.

A microelectromechanical systems (MEMS) device including a substrate, a membrane layer and a plurality of patterned backplates is provided. The membrane layer is disposed on the substrate and has a plurality of corrugated structures. A top surface of the membrane layer has a rounded-corner feature, and a bottom surface of the membrane layer has a sharp-corner feature. The plurality of patterned backplates are disposed above the membrane layer. A manufacturing method of a MEMS device is also provided.

A MEMS module includes: a first MEMS element and a second MEMS element each including a movable portion which is a portion of a substrate including a hollow portion formed therein, the movable portion configured to warp in shape according to an air pressure difference between an internal air pressure inside the hollow portion and an external air pressure outside the hollow portion; and an electronic component configured to calculate a change in external air pressure outside the substrate by using an amount of warpage of the movable portion of at least one of the first MEMS element and the second MEMS element, wherein the amount of warpage of the movable portion according to the external air pressure differs between the first MEMS element and the second MEMS element.