SURFACE IMPURITY REMOVAL OF III-V GROUP SEMICONDUCTOR ELEMENT

摘要

PURPOSE: To remove impurities on a surface of a III-V group semiconductor element and grow a high quality of epitaxial layer thereon by exposing to hydrogen plasma the semiconductor element, having an exposed surface of a specific time, etching the element with the use of Cl2 for a specific time and then annealing the element at a specific time for a specific time. CONSTITUTION: A semiconductor element 10, having a III-V group surface layer has a semiconductor layer 13 and a mask layer 11 of a material, which is other than the III-V group, and the semiconductor layer 13 is exposed in its predetermined surface zone 12. A semiconductor element 10 is exposed to hydrogen plasma for 20-120 minutes within a vacuum-excited plasma chamber and then etched for 1-5 minutes in a temperature range of 250-450 deg.C with the chamber interior kept at a vacuum level. The element is then transferred into a vacuum- kept annealing chamber and heated at a temperature of 200-600 deg.C for 5-60 minutes for annealing. Further the semiconductor element 10 is transferred into a growth chamber in a vacuum. Thereby a high quality semiconductor layer 14 can be epitaxially re-grown on a cleaned surface of the element.