Abstract: A semiconductor strain sensor having a strain sensor chip composed of a semiconductor substrate having a piezoresistive element as a strain detection section. The semiconductor strain sensor has a stable characteristic for a long period of time and a stable conversion factor of a strain generated in the strain sensor chip corresponding to a strain of an object to be measured, within a strain range of a size to be measured. The strain sensor chip is bonded to a metal base plate with a metal bonding material. The metal base plate has two or four extending members, which protrude from a side of the strain sensor chip for attaching the strain senor chip to the object to be measured. Preferably, a groove is arranged between a metal base plate undersurface area, which corresponds to the bonding area where the strain sensor chip is bonded to the metal base plate, and the undersurfaces of the extending members, and a protruding section sandwiched by the grooves is arranged on the undersurface of the metal base plate.

Abstract: A semiconductor strain sensor having a strain sensor chip composed of a semiconductor substrate having a piezoresistive element as a strain detection section. The semiconductor strain sensor has a stable characteristic for a long period of time and a stable conversion factor of a strain generated in the strain sensor chip corresponding to a strain of an object to be measured, within a strain range of a size to be measured. The strain sensor chip is bonded to a metal base plate with a metal bonding material. The metal base plate has two or four extending members, which protrude from a side of the strain sensor chip for attaching the strain senor chip to the object to be measured. Preferably, a groove is arranged between a metal base plate undersurface area, which corresponds to the bonding area where the strain sensor chip is bonded to the metal base plate, and the undersurfaces of the extending members, and a protruding section sandwiched by the grooves is arranged on the undersurface of the metal base plate.

Abstract: An SAL-type magnetoresistive playback head that is highly sensitive and that limits Barkhausen noise is provided by optimizing the magnetic properties of the permanent magnet film. On top of a lower insulating layer are stacked a soft magnetic bias film (SAL film), a magnetic separating film (shunt film), a magnetoresistive film (MR film), and an upper insulating layer, in that order. The outer sides of the track of the MR film are in direct contact with the permanent magnet film or in indirect contact via a base film. Alternatively, the present invention relates to a spin-valve magnetoresistive playback head. On top of a lower insulating layer are stacked an anti-ferromagnetic film, a fixed magnetizing film, a magnetic separating film, a movable magnetizing film (MR film), and an upper insulating layer, in that order. The outer sides of the track of the movable magnetizing film are in direct contact with the permanent magnet film or in indirect contact via a base film.