To protect a bridging part from being damaged in the case of separating the semiconductor wafer into the units of the microbridge sensor after arranging and forming a thin-film sensor part corresponding to a plurality of microbridge sensors in the same semiconductor wafer.

A side surface 16 of a semiconductor substrate 1A (111) of a microbridge sensor S1 is formed by a surface {111}. Therefore, a thin-film sensor part 10 for each of a plurality of microbridge sensors S1 is arranged and formed on a common semiconductor wafer (110), thus achieving breaking without causing a bridging part from being damaged since the separation surface is the surface {111} when separating the semiconductor wafer (110) into the units of the microbridge sensor S1.