Abstract: A process is disclosed for producing pn junctions and p-i-n junctions from group III nitride compound semiconductor materials. The process comprises growing of pn junctions and p-i-n junctions by hydride vapor phase epitaxy employing hydride of nitrogen (ammonia, hydrozine) as a source of nitrogen and halides of group III metal as a source of metal. Mg is used as acceptor impurity to form p-type III-V nitride layers. The preferred sources for Ga and Al are Ga and Al metals, respectively. The process is carried out in the temperature range from 900 to 1200° C.