主权项 |
1. A semiconductor device, comprising:
a semiconductor substrate comprised of a semiconductor layer; an element region that is prevented from receiving stresses applied to the semiconductor device and on which semiconductor elements sensitive to stress are formed, the element region comprising a current mirror circuit and being formed in the semiconductor layer at a preselected depth from a surface thereof and arranged substantially at a center of the semiconductor layer; a buffer region formed around the element region for absorbing stresses applied to the semiconductor device to prevent the element region from receiving the stresses, the buffer region comprising a trench formed in the semiconductor layer and a filler material filled in the trench and having a Young's modulus lower than a Young's modulus of the semiconductor layer; and a semiconductor element formation region on which semiconductor elements not sensitive to stress are formed, the semiconductor element formation region being formed in the semiconductor layer at a preselected depth from the surface thereof, the semiconductor element formation region extending around the buffer region with the buffer region disposed between the semiconductor element formation region and the element region, and the trench of the buffer region extending into the semiconductor layer so that a depth of the trench from the surface of the semiconductor layer is greater than the preselected depth of each of the element region and the semiconductor element formation region and so that a portion of the semiconductor layer exists under the filled trench of the buffer region. |