Confined crystal growth techniques

Epitaxial crystal growth methods such as molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) have advanced to the point that active regions of essentially arbitrary thicknesses can be prepared (see Thin films, film deposition techniques). Most semiconductors used for lasers are cubic crystals where the lattice constant, the dimension of the cube, is equal to two atomic plane distances. When the thickness of this layer is reduced to dimensions on the order of 0.01 )J.m, between 20 and 30 atomic plane distances, quantum mechanics is needed for an accurate description of the confined carrier energies (11). Such layers are called quantum wells and the lasers containing such layers in their active regions are known as quantum well lasers (12). 

Metallic carbides, nitrides, and oxides are used industrially in many applications their physical properties are also of intrinsic interest. This section pinpoints various preparative techniques and reviews methods of crystal growth for this group of compounds. More detailed discussion is found in the reviews cited and in the references therein. The discussion is confined to binary compounds, M Xi, (M is a cation X = C, N, or O a and b are simple integers) that display metallic properties the very numerous ternaries MoMcXj, (M, M being different cations) cannot be described in this brief presentation. 

Chapter 1 covers experimental techniques widely used in studies of polymer crystalhzation. Chapter 2, Chapter 3, Chapter 4, and Chapter 5 are devoted to the structure of crystalline polymers and also to the kinetics of nucleation and growth of the crystaUine phase. Chapter 6 is focused on molecular modeling of polymer crystallization, whereas Chapter 7 describes overah crystalhzation kinetics, with special reference to the theories widely used in practice. Chapter 8 covers the subject of epitaxy. Chapter 9 is dedicated to melting of polymer crystals. Chapter 10, Chapter 11, and Chapter 13 describe the crystahization in copolymers, miscible and immiscible polymer blends, and also polymer composites. Chapter 12 is focused on phenomena related to the confinement of polymer chains. Chapter 14 describes the effect of flow on crystahization, and finally Chapter 15 covers the crystalhzation in processing conditions. 

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