Abstract: A semiconductor device is provided. The semiconductor device includes a first stacked structure including a plurality of first insulating patterns and a plurality of first semiconductor patterns alternately stacked on a substrate, the first stacked structure extending in a first direction parallel to an upper surface of the substrate, a first conductive pattern on one side surface of the first stacked structure, the first conductive pattern extending in a second direction crossing the upper surface of the substrate, and a first ferroelectric layer between the first stacked structure and the first conductive pattern, the first ferroelectric layer extending in the second direction, wherein each of the first semiconductor patterns includes a first impurity region, a first channel region and a second impurity region which are sequentially arranged along the first direction.

Abstract: A method according to an embodiment is for recovering a valuable metal from a waste electrode material of a lithium secondary battery by using lithium carbonate. An anode-cathode mixed electrode material that has been separated by draining, crushing, screening, and sorting a waste lithium secondary battery is preprocessed. A precipitation operation performed by adding lithium carbonate (Li2CO3) to a metal melt acquired by performing sulfuric acid dissolution using sulfuric acid. A valuable metal such as nickel, cobalt, manganese, aluminum, and copper is recovered as a residue in the form of a carbonate composite, and a lithium sulfate (Li2SO4) aqueous solution including lithium is recovered as a filtrate.