Force sensor and method of manufacturing the same

A method of manufacturing a force sensor, the method comprising the steps of:

• forming a number of sensor structures on one of front and rear panel surfaces of a sensor substrate panel having displacement portions, the sensor structures each including a plurality of piezoresistance elements, an electrical resistance of each piezoresistance element changing in accordance with an amount of displacement of the displacement portion that is displaced, a sensor-side support, at least part of the sensor-side support being positioned so as to be superposed with the plurality of piezoresistance elements in plan view, the sensor-side support supporting the displacement portion such that the displacement portion is able to be disposed, and a plurality of sensor-side electrically connecting portions positioned closer to a periphery of each sensor structure than the sensor-side support is, the plurality of sensor-side electrically connecting portions each being electrically connected to a corresponding one of the plurality of piezoresistance elements, the plurality of sensor-side electrically connecting portions being provided along the periphery of each sensor structure so as to surround an outer periphery of the sensor-side support, the plurality of sensor-side electrically connecting portions being separated from one another at positions that do not cross a virtual line passing through a center of the pressure receiving unit and a center of each of the plurality of piezoresistance elements, the sensor-side support being formed to have a shape having a closed inner peripheral edge that surrounds an entire periphery of the displacement portion in plan view;
• forming a number of base structures on one of front and rear panel surfaces of a base substrate panel, the base structures each including a plurality of base-side electrically connecting portions corresponding to the plurality of sensor-side electrically connecting portions, a plurality of electrode pads formed at ends of electrical wiring extending from the base-side electrically connecting portions so as to be wire-bondable, and a base-side support positioned in an area surrounded by the plurality of base-side electrically connecting portions so as to correspond to the sensor-side support;
• joining the sensor substrate panel and the base substrate panel to each other while pressing the sensor substrate panel and the base substrate panel against each other and simultaneously joining the plurality of sensor-side electrically connecting portions to the base-side electrically connecting portions and the sensor-side supports to the base-side supports in an atmosphere in which the temperature is in a range from room temperature to a temperature lower than 250° C.;
• forming a number of pressure receiving units on the other panel surface out of the front and rear panel surfaces of the sensor substrate panel, an external load to be applied to a displacement portion of each sensor structure through a corresponding one of the pressure receiving units;
• and
• cutting the sensor substrate panel and the base substrate panel into chips each including a pair of the sensor structure and the base structure.