CRYSTALLIZATION FROM MELTS AS A METALLURG ICAL PROCESS

In metallurgy crystallization methods are used in different technologi cal processes (refining by segregation, directed criytallization of in gots, continuous casting, zone melting, Czochralski-Method, Bridgman-M ethod an so on). The growing of GaAs monocrystals by the Gradient-Free ze-Method is described in this contribution as a special example and t he thermal regime (coordination system: G(x) = dT/dx; v = dx/dt; G(t) = dT/dt) is compared with other crystallization techniques. Selected a spects of thermal conditions of crystal growth in a multi zone furnace are explained by means of results of model contemplations.