Patent ID: 7040165

Claim:
A semiconductor mechanical quantity sensor comprising: a first layer formed by a silicon substrate; a second layer formed by an insulation layer disposed on said first layer; a third layer formed by a silicon layer disposed on said second layer; a fourth layer formed by an insulation layer disposed on said third layer; and a fifth layer formed by a silicon layer disposed on said fourth layer, wherein: said third layer is formed by a polysilicon layer being doped with high density impurities and configured with a predetermined pattern in a direction parallel with said first layer, said fifth layer is provided with a weight being movable due to the effect of the mechanical quantity, a movable electrode formed on said weight, a fixed electrode facing said movable electrode, and electric routing paths being separated from said weight and extending in a direction perpendicular to said first layer, and said polysilicon layer and said electric routing paths are electrically connected via a bottom contact for an electric connection, the bottom contact being formed at a predetermined position on said fourth layer while passing through the fourth layer.