Physical quantity sensor with son structure, and manufacturing method thereof

A method of manufacturing a physical quantity sensor with a SON structure, the method comprising:

• a step of forming a trench hole group in a surface layer of a semiconductor wafer, and a trench groove, whose plan form is a ring with a place in which one portion is cut, distanced from the trench hole group in an outer peripheral portion of the trench hole group;
• a step of performing an annealing, causing trench holes of the trench hole group to deform, thus forming one large cavity configuring an SON structure;
• and
• a step of forming a Wheatstone bridge in a semiconductor layer that forms a diaphragm above the cavity, forming an electronic circuit in an outer peripheral portion of the trench groove, and forming a wire that connects the Wheatstone bridge and electronic circuit on the place in the ring in which one portion is cut.

A method of manufacturing a physical quantity sensor with a SON structure, the method comprising:

• a step of forming a first trench hole group in a surface layer of a semiconductor wafer, and a second trench hole group, whose plan form is a ring or a ring with a place in which one portion is cut, distanced from the first trench hole group in an outer peripheral portion of the first trench hole group;
• a step of performing an annealing, causing first trench holes of the first trench hole group and second trench holes of the second trench hole group to deform, thus forming a first cavity configuring a first SON structure and a second cavity configuring a second SON structure;
• and
• a step of forming a Wheatstone bridge in a semiconductor layer that forms a diaphragm above the first cavity, forming an electronic circuit in an outer peripheral portion of the second cavity, and forming a wire that connects the Wheatstone bridge and electronic circuit above the second cavity or across the place in which the second cavity is cut.