Alternating layer and island growth of Pb on Si by spontaneous quantum phase separation.
نویسندگان
چکیده
Real-time in situ x-ray studies of continuous Pb deposition on Si(111)-(7x7) at 180 K reveal an unusual growth behavior. A wetting layer forms first to cover the entire surface. Then islands of a fairly uniform height of about five monolayers form on top of the wetting layer and grow to fill the surface. The growth then switches to a layer-by-layer mode upon further deposition. This behavior of alternating layer and island growth can be attributed to spontaneous quantum phase separation based on a first-principles calculation of the system energy.
منابع مشابه
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عنوان ژورنال:
- Physical review letters
دوره 90 7 شماره
صفحات -
تاریخ انتشار 2003