Strain and pressure sensing device, microphone, method for manufacturing strain and pressure sensing device, and method for manufacturing microphone

A method for manufacturing a strain and pressure sensing device, comprising:

• forming a transistor on a semiconductor substrate;
• forming a sacrificial layer on the transistor;
• forming a sensing unit on the sacrificial layer, and
• removing the sacrificial layer,
• the sensing unit including a diaphragm and a strain sensing element, the diaphragm being separated from the transistor, a space being provided between the transistor and the diaphragm, the strain sensing element being fixed to the diaphragm, and the strain sensing element including a first magnetic layer, a second magnetic layer;
• and a nonmagnetic intermediate layer provided between the first magnetic layer and the second magnetic layer, wherein
• the first magnetic layer includes at least one selected from a group consisting of Co, Fe and Ni, and the second magnetic layer includes at least one selected from a group consisting of Co, Fe and Ni,
• one of the first magnetic layer and the second magnetic layer is positioned between the diaphragm and the other one of the first magnetic layer and the second magnetic layer,
• an electrical resistance of the sensing unit changes in accordance with a deformation of the diaphragm, and
• the first magnetic layer overlaps a part of the diaphragm, and the diaphragm includes a region not overlapping the first magnetic layer.