A semiconductor device is provided that simplifies wiring pattern and is capable of being etched through an etching hole as a concavity is produced over a short time period. A dielectric film 12 is formed so as to shield the concavity formed upon the upper surface of a silicon substrate 10. A circuit pattern that has a thermoelectric conversion element 18 is formed upon the dielectric film. The upper surface of the silicon wafer becomes a (100) surface, and a first etching hole 16 extending in the direction of the silicon substrate and a second etching hole 17 extending in the direction are formed. These holes intersect in a cross shape. Shapes of the first and second etching holes become parallelograms which have oblique sides tilted with respect to and . Imaginary rectangles passing though the vertices of the first and second etching holes are continuous. As a cross shape is removed from the silicon substrate, etching is rapid due to the appearance of (411) surfaces at the intersecting part.