Mitsubishi Denki Kabushiki Kaisha

Other

Kunihiro Nakamura

Yasuo Yamaguchi

Teruya Fukaura

Shiro Yamasaki

An acceleration sensor includes an acceleration sensor element and a frame portion surrounding the element. The sensor element and the frame portion are located on a major surface of a substrate. An intermediate layer is formed on the frame portion. A cap portion is bonded to the intermediate layer, thereby sealing-off the acceleration sensor element. Grooves in the form of a frame are provided in the frame portion and the intermediate layer, respectively, and located at positions generally identical to each other with regard to the major surface direction of the substrate.

Acceleration sensor

Provided is a method of manufacturing an acceleration sensor capable of preventing bonding of a movable electrode and a fixed electrode. A stain filmfor reducing bonding adsorption force is formed on side surfaces of a movable electrode, fixed electrodesandand a frame portionIn the case in which the movable electrodeand the fixed electrodesandare to be formed of a silicon substrate, it is preferable that an insulating film having irregular bonding of silicon atoms and oxygen atoms and irregular bonding of silicon atoms and nitrogen atoms should be employed for the stain filmfor example. The formation of the stain filmcan suppress the bonding between the movable electrodeand the fixed electrodesandeven if Coulomb force is generated between both electrodes when the silicon substrate and a back side substrateare joined by using an anode junction method.

Method of manufacturing acceleration sensor

In manufacturing hermetically sealed semiconductor devices, a plurality of generally rectangular openings are first formed into a matrix pattern in a cap silicon wafer so that the plurality of generally rectangular openings are separated by a plurality of row segments extending in a first direction and a plurality of column segments extending in a second direction perpendicular to the first direction. On the other hand, a plurality of semiconductor elements each having a plurality of electrode portions are bonded to a semiconductor wafer. After each of the plurality of generally rectangular openings has been aligned with the plurality of electrode portions of at least one of the plurality of semiconductor elements, the cap wafer is bonded to the plurality of semiconductor elements.

Method of manufacturing semiconductor devices

Provided is a method of manufacturing an acceleration sensor capable of preventing bonding of a movable electrode and a fixed electrode. A stain film for reducing bonding adsorption force is formed on side surfaces of a movable electrode , fixed electrodes and and a frame portion . In the case in which the movable electrode and the fixed electrodes and are to be formed of a silicon substrate, it is preferable that an insulating film having irregular bonding of silicon atoms and oxygen atoms and irregular bonding of silicon atoms and nitrogen atoms should be employed for the stain film , for example. The formation of the stain film can suppress the bonding between the movable electrode and the fixed electrodes and even if Coulomb force is generated between both electrodes when the silicon substrate and a back side substrate are joined by using an anode junction method.

In order to provide a semiconductor device which has a bonding layer capable of providing electrical continuity between the cap and the semiconductor substrate, the semiconductor device comprises a semiconductor substrate whereon an element is formed on one principal plane thereof and a cap which hermetically seals the element so that a space is formed over the element, while the element is sealed by bonding a laminated bonding layer, which is formed around the element provided on the principal plane, and an Ni layer formed on the cap, wherein the laminated bonding layer is constituted from a first polysilicon layer which is doped with an impurity, an insulation layer and a second polysilicon layer which is not doped with an impurity, while the first polysilicon layer and the second polysilicon layer contact with each other in a part thereof so that the impurity diffuses through the contact area from the first polysilicon layer into the second polysilicon layer.

Semiconductor device

Providing an acceleration sensor in which a base portion and a cap portion are bonded to each other and a sensor portion is sealed off between these two, and which has an improved bonding strength between the base portion and the cap portion. A sensor portion and a frame portion surrounding a periphery of the sensor portion are disposed on a semiconductor substrate. A base portion is comprised, where a diffusion preventing layer and a non-doped polycrystalline silicon layer are stacked one atop the other on the frame portion. A cap portion is comprised, where a nickel layer is formed on a base unit. The non-doped polycrystalline silicon layer of the base portion and the nickel layer of the cap portion are bonded to each other by eutectic bonding.

Growing community of inventors

Tokyo, Japan

Kunihiro Nakamura