Abstract: A method of forming a pn junction with a Group IIB-VIB compound semiconductor containing Zn is disclosed, the method including preparing an n type semiconductor region either locally or entirely in a Group IIB-VIB compound semiconductor crystal obtained by relying on a crystal growth method in liquid phase using a temperature difference technique, and subjecting this crystal to a thermal annealing in a Zn solution or in a Zn atmosphere to produce an n type region. Crystal growth is conducted while controlling the vapor pressure of the constituent Group IVB element to produce a p type region. A combination of all these steps gives a more stable pn junction.

Abstract: A method of manufacturing a pn junction in a substantially n-type ZnSe compound semiconductor crystal grown by relying on a liquid growth method using temperature difference technique, by diffusing therein gold which is a p-type impurity or by forming therein a gold alloy in an inert gas atmosphere. This impurity has such a high diffusion velocity as can suppress the vaporization, from ZnSe crystal, of Se atoms having a vaporization speed lower than the diffusion speed of gold, and thus desired pn junction can be formed.