Provided is a detector having a transistor or resistor structure. When an electrode is exposed to a detected solution, such as blood, a variation in current flowing through the detected solution may be greater than a variation in the electrical characteristics of the detector caused by a variation in the physical properties of semiconductor so that it is difficult to detect whether a bio-particle is contained in the detected solution. In order to solve this problem, a detection portion and an electrical measurement portion are separately formed, and the detection portion is processed with the bio-particle and then post-processed. Subsequently, the detection portion and the electrical measurement portion are bonded to each other using, for example, a laminating process, and the detector measures a detection value.