For a liquid discharge head substrate and a liquid discharge head using the same

A base for a liquid discharge head includes a heat element which forms an exothermic portion, an electrode wire that is electrically connected with the heat element, an insulative protective layer provided above the heat generating resistive element and the electrode wire and an upper protective layer provided on the protective layer. The upper protective layer is made from a TaSi alloy containing 22 at. % or more Si.