Patent attributes
A semiconductor device that writes data to, instead of a defective memory cell, another memory cell is provided. The semiconductor device includes a first circuit and a second circuit over the first circuit; the first circuit corresponds to a memory portion and includes a memory cell and a redundant memory cell; a second circuit corresponds to a control portion and includes a third circuit and a fourth circuit. The memory cell is electrically connected to the third circuit, the redundant memory cell is electrically connected to the third circuit, and the third circuit is electrically connected to the fourth circuit. The fourth circuit has a function of sending data to be written to the memory cell or the redundant memory cell to the third circuit, and the third circuit has a function of bringing the memory cell and the fourth circuit into a non-conduction state and the redundant memory cell and the fourth circuit into a conduction state to send the data to the redundant memory cell when the memory cell is a defective cell.
