Abstract: A humidity sensing portion is mounted in a gap between a first opposite member and a second opposite member. Metal joints and dummy joints are provided in the gap between the first opposite member and the second opposite member, and the two opposite members are fixed to each other through the metal joints and the dummy joints. Since only the metal joints and the dummy joints are present in the gap between the two opposite members, gas to be measured is easily introduced into the humidity sensing portion, and the sensing response to the humidity change is improved.

Abstract: In a pressure detection device which is provided in an intake pressure measurement apparatus, a detection space surrounded by an outer wall portion is formed in a housing, and an inner wall portion is formed integrally in the detection space such that both end portions are connected to the outer wall portion. The inner wall portion has a cylindrical shape, and a sensor storage portion is formed between the inner wall portion and the outer wall portion. In the sensor storage portion, a pressure sensor is disposed in a region with the least influence of thermal stress at a position closer to the inner wall portion than the outer wall portion.

Abstract: A first sealing layer having a frame-like shape and a first contact layer are formed on a back surface of a frame portion of a sensor substrate. The first contact layer is separated from the first sealing layer, extends through a functional member and an insulation layer, and is electrically connected to the functional member and a first base member. A second sealing layer and a second contact layer are formed on a surface of a wiring substrate. The second sealing layer faces the first sealing layer. The second contact layer is separated from the second sealing layer, extends through the insulation layer, and is electrically connected to the second base member. The sealing layers are eutectically bonded to each other. The contact layers are electrically connected to each other, and thereby the first and second base members and the frame portion have the same potential.

Abstract: A semiconductor pressure sensor includes a cavity disposed in one silicon substrate of a SOI substrate having two silicon substrates bonded to each other with an oxide film therebetween and a diaphragm formed from the other silicon substrate and the oxide film, wherein the oxide film, bordering the cavity, of the diaphragm includes an arc-shaped section at the boundary portion to the one silicon substrate defining the inner wall side surface of the cavity, the arc-shaped section having the same width as the width of the cavity at a desired section in the one silicon substrate and reducing the width of the cavity from the boundary portion toward the diaphragm center.

Abstract: A semiconductor pressure sensor includes a cavity disposed in one silicon substrate of a SOI substrate having two silicon substrates bonded to each other with an oxide film therebetween and a diaphragm formed from the other silicon substrate and the oxide film, wherein the oxide film, bordering the cavity, of the diaphragm includes an arc-shaped section at the boundary portion to the one silicon substrate defining the inner wall side surface of the cavity, the arc-shaped section having the same diameter as the diameter of the cavity in the one silicon substrate and reducing the cavity diameter from the boundary portion toward the diaphragm center.