Substrate Engineering--paving the Way to Epitaxy

Book excerpt: Epitaxial growth has always been a marriage of convenience between film and substrate. More and more frequently, however, it is impractical to use the same material for both film and substrate because it is not available as large single crystals, it is prohibitively expensive, or its properties are ill-suited for the intended application. To meet these challenges, many strategies have been pursued to achieve highly oriented or single-crystal thin films via epitaxy. Crystalline films have been mechanically bonded to other materials to form composite substrates. Crystals have been cut and rewelded, patterned and regrown, buffer layered and repolished. Each strategy has met with fundamental challenges including lattice mismatch, chemical incompatibility, differences in thermal expansion, and structural dissimilarity. This book, first published in 2000, focuses on developments in novel substrate engineering which enable improved epitaxy. Topics include: biaxially textured substrates for high-Tc-coated conductors; surfaces for oxide epitaxy; wafer bonding and lift off; lattice mismatch engineering; substrate engineering and solid-phase recrystallization and epitaxy.