Abstract: An automatically passivated n-p junction is formed from a p-type body containing Group II and Group VI elements, one of which is mercury. A passivation layer is then formed having at least one window provided therein on a surface of the p-type body. The p-type body is then subjected to a reactive ion etching process using the passivation layer as a mask to form the n-p junction. Ohmic contacts are then formed on the n-type and p-type regions. The method may be extended to form an array of n-p junctions on a semiconductor body having a plurality of p-type material layers.