IN-SITU SURFACE PASSIVATION OF III-V SEMICONDUCTORS IN MOVPE BY AMORPHOUS AS AND P LAYERS

A new process for chemical passivation of III-V semiconductor surfaces in metalorganic vapour phase epitaxy (MOVPE) is developed. A passivat ion layer is deposited directly after growth in the reactor. It consis ts of amorphous arsenic or a double-layer package of amorphous phospho rus and arsenic, which are grown by photo-decomposition of the group-V hydrides. These layers (caps) serve to protect the surfaces against c ontamination in air after removing the samples from the MOVPE growth r eactor. Such passivation is applicable e.g. for a two-step epitaxy or for further surface characterizations.