A target (51A; 51C; 51D; 51E) comprising a target material comprising lithium for a neutron-generating device configured to generate neutrons by a 7 Li(p,n) 7 Be reaction when the target material is irradiated with proton beams accelerated by an accelerator, the target (51A; 51C; 51D; 51E) comprising: a metal substrate (52A; 52C; 52D; 52E) that retains the target material; and a metal thin film for sealing configured to seal the target material onto the metal substrate (52A; 52C; 52D; 52E) at a retention surface side holding the target material, the metal substrate (52A; 52C; 52D; 52E) comprising: on the retention surface side, a frame portion; and an embossed structure (52b, 52c) comprising: a plurality of island portions surrounded by the frame portion and regularly arranged in the lateral and longitudinal directions, the island portions having the same height as the frame portion; and the rest of the embossed structure (52b, 52c) comprising a recessed portion that is created by decreasing a thickness of a region other than the frame portion and the plurality of island portions by a thickness of the target material, wherein the metal thin film for sealing is bonded by means of hot isostatic pressing to surfaces of the frame portion and the plurality of island portions, and wherein the metal thin film for sealing is configured to seal the target material onto the recessed portion of the metal substrate (52A; 52C; 52D; 52E). a metal substrate (52A; 52C; 52D; 52E) that retains the target material; and a metal thin film for sealing configured to seal the target material onto the metal substrate (52A; 52C; 52D; 52E) at a retention surface side holding the target material, the metal substrate (52A; 52C; 52D; 52E) comprising: on the retention surface side, a frame portion; and an embossed structure (52b, 52c) comprising: a plurality of island portions surrounded by the frame portion and regularly arranged in the lateral and longitudinal directions, the island portions having the same height as the frame portion; and the rest of the embossed structure (52b, 52c) comprising a recessed portion that is created by decreasing a thickness of a region other than the frame portion and the plurality of island portions by a thickness of the target material, a frame portion; and an embossed structure (52b, 52c) comprising: a plurality of island portions surrounded by the frame portion and regularly arranged in the lateral and longitudinal directions, the island portions having the same height as the frame portion; and the rest of the embossed structure (52b, 52c) comprising a recessed portion that is created by decreasing a thickness of a region other than the frame portion and the plurality of island portions by a thickness of the target material, a plurality of island portions surrounded by the frame portion and regularly arranged in the lateral and longitudinal directions, the island portions having the same height as the frame portion; and the rest of the embossed structure (52b, 52c) comprising a recessed portion that is created by decreasing a thickness of a region other than the frame portion and the plurality of island portions by a thickness of the target material, wherein the metal thin film for sealing is bonded by means of hot isostatic pressing to surfaces of the frame portion and the plurality of island portions, and wherein the metal thin film for sealing is configured to seal the target material onto the recessed portion of the metal substrate (52A; 52C; 52D; 52E).