A semiconductor light emitting element of nitride compound semiconductors excellent in cleavability, heat radiation and resistance to leakage is made by epitaxially grow a nitride compound semiconductor layers on a substrate of sapphire, for example, and thereafter separating the substrate. For separating the substrate, there are a technique using a abruption mechanism susceptible to a stress such as a "lift-off layer" and a recesses on a substrate. A technique using laser light to cause a local dense heat stress at the abruption mechanism is effective. A nitride compound semiconductor obtained by separating the substrate may be used as a new substrate to epitaxially grow high-quality nitride compound semiconductors thereon.