A method for manufacturing an optical device includes: preparing a semiconductor substrate that includes a portion corresponding to a base, a movable unit, and an elastic support portion; forming a first resist layer in a region corresponding to the base on a surface of a first semiconductor layer which is opposite to an insulating layer; forming a depression in the first semiconductor layer by etching the first semiconductor layer using the first resist layer as a mask; forming a second resist layer in a region corresponding to a rib portion on a bottom surface of the depression, a side surface of the depression, and the surface of the first semiconductor layer which is opposite to the insulating layer; and forming the rib portion by etching the first semiconductor layer until reaching the insulating layer using the second resist layer as a mask.

A contact having a first contact member having an exposed surface, the exposed surface having irregularities, undulations, or asperities that form one or more high points and low points on the exposed surface, a second contact member having a contact base surface, a plurality of electrically conductive flexures extending from the contact base surface, and when the first contact member is positioned adjacent to the second contact member in a closed position in which the contact base surface of the second contact member is not in electrical contact with the one or more high points on the exposed surface of the first contact member, each flexure of the plurality of flexures is in electrical contact with the exposed surface of the first contact member.

In an optical device, when viewed from a first direction, first, second, third, and fourth movable comb electrodes are respectively disposed between a first support portion and a first end of a movable unit, between a second support portion and a second end of the movable unit, between a third support portion and the first end, and between a fourth support portion and the second end of the movable unit. The first and second support portions respectively include first and second rib portions formed so that the thickness of each of the first and second support portions becomes greater than the thickness of the first torsion bar. The third and fourth support portions respectively include third and fourth rib portions formed so that the thickness of each of the third and fourth support portions becomes greater than the thickness of the second torsion bar.

A method of forming an ultrasonic transducer device includes forming a patterned metal electrode layer over a substrate, the patterned metal electrode layer comprising a lower layer and an upper layer formed on the lower layer; forming an insulation layer over the patterned metal electrode layer; and planarizing the insulation layer to the upper layer of the patterned metal electrode layer, wherein the upper layer comprises a electrically conductive material that serves as a chemical mechanical polishing (CMP) stop layer that has CMP selectivity with respect to the insulation layer and the lower layer, and wherein the upper layer has a CMP removal rate slower than that of the insulation layer.

A triple-membrane MEMS device includes a first membrane, a second membrane and a third membrane spaced apart from one another, wherein the second membrane is between the first membrane and the third membrane, a sealed low pressure chamber between the first membrane and the third membrane, a first stator and a second stator in the sealed low pressure chamber, and a signal processing circuit configured to read-out output signals of the triple-membrane MEMS device.

A method for manufacturing an optical device includes: preparing a semiconductor substrate that includes a portion corresponding to a base, a movable unit, and an elastic support portion; forming a first resist layer in a region corresponding to the base on a surface of a first semiconductor layer which is opposite to an insulating layer; forming a depression in the first semiconductor layer by etching the first semiconductor layer using the first resist layer as a mask; forming a second resist layer in a region corresponding to a rib portion on a bottom surface of the depression, a side surface of the depression, and the surface of the first semiconductor layer which is opposite to the insulating layer; and forming the rib portion by etching the first semiconductor layer until reaching the insulating layer using the second resist layer as a mask.

An optical device includes a support portion a movable unit and a pair of torsion bars disposed on both sides of the movable unit on a first axis. The movable unit includes a main body portion, a ring-shaped portion surrounding the main body portion when viewed from a predetermined direction perpendicular to the first axis, two connection portions connecting the main body portion and the ring-shaped portion to each other, and a rib portion provided to the main body portion. Each of the two connection portions includes two connection regions that are separated from each other by a space and the each of the two connection region connects the main body portion and the ring-shaped portion to each other. The rib portion includes four extending portions radially extending between a center of the main body portion and the four connection regions respectively when viewed from the predetermined direction.

A triple-membrane MEMS device includes a first membrane, a second membrane and a third membrane spaced apart from one another, wherein the second membrane is between the first membrane and the third membrane, a sealed low pressure chamber between the first membrane and the third membrane, a first stator and a second stator in the sealed low pressure chamber, and a signal processing circuit configured to read-out output signals of the triple-membrane MEMS device.

A microelectromechanical system (MEMS) sensor assembly comprises a substrate, a bump stopper extending from the substrate, and a sensor suspended relative to the substrate. The sensor is configured to move relative to the substrate, wherein the bump stopper is configured to restrain the sensor travel distance and prevent contact between the sensor and the substrate. The bump stopper has a surface facing the sensor, wherein an area of contact between the sensor and the surface is less than the total area of the surface.

An optical device includes a support portion, a movable portion; and a pair of torsion bars. An optical function portion is provided on one surface of the movable portion and a rib portion is provided on the other surface of the movable portion. The rib portion includes eight extending portions of first to eighth extending portions. When setting directions in which the first to eighth extending portions extend as first to eighth extending directions respectively, and setting an angle between the first and second extending directions as a first angle, an angle between the third and fourth extending directions as a second angle, an angle between the fifth and sixth extending directions as a third angle, and an angle between the seventh and eighth extending directions as a fourth angle, each of the first and second angle is larger than each of the third and fourth angle.