A chalcogenide layer includes a composition of compounds having the formula M.sub.mX.sub.1-m, where M denotes one or more elements selected from the group consisting of group IVb elements of the periodic system, group Vb elements of the periodic system and transition metals, X denotes one or more elements selected from the group consisting of S, Se and Te, and m has a value of between 0 and 1. The chalcogenide layer further includes an oxygen or nitrogen content in the range from 0.001 atomic % to 75 atomic %.