PREPARATION OF NANOMETER-SCALE WINDOWS IN SIO2 FOR SELECTIVE EPITAXIAL-GROWTH OF SI BASED DEVICES

Three methods are presented for preparation of windows in SiO2 for sel ective epitaxial growth of Si based devices. The window patterns are d efined using e-beam lithography and the structures are grown with chem ical vapour deposition or molecular beam epitaxy. One method is based on wet etching; the other two are based on reactive ion etching. The r esulting window sizes and quality of epitaxial growth are evaluated us ing transmission electron microscopy of grown structures. Each of the techniques results in high quality selective epitaxial growth. With a new post-etching treatment in a Cl-2 plasma high quality growth is dem onstrated in windows as small as 46 nm.