A semiconductor integrated device is provided with: a die having a body of semiconductor material with a front surface, and an active area arranged at the front surface; and a package having a support element carrying the die at a back surface of the body, and a coating material covering the die. The body includes a mechanical decoupling region, which mechanically decouples the active area from mechanical stresses induced by the package; the mechanical decoupling region is a trench arrangement within the body, which releases the active area from an external frame of the body, designed to absorb the mechanical stresses induced by the package.