FORMATION OF DIAMOND NUCLEI UNDER THE GROWTH OF FILMS AND CRYSTALS FROM THE GAS-PHASE

Kinetic conditions of equilibrium (critical) formation of diamond nucl ei and non-equilibrium growth of macroscopic diamond crystals and film s by the polycondensation of small carbon-containing molecules are con sidered. There are essential distinctions in macrokinetic conditions f or formation of nuclei and macrocrystal growth when the same microkine tic conditions of diamond substance formation occur. The diamond macro crystals can grow only under conditions of non-equilibrium in open cat alytic systems, but nuclei can be formed in closed ones until the esta blishment of the equilibrium. A method of estimating equilibrium nucle us parameters is proposed, depending on the conditions of their format ion under a polycondensation process. According to these calculations, the equilibrium nuclei are thin epitaxial films having a ratio of the thickness to the diameter equal to 2 x 10(-4). The thickness of the n uclei decreases by 10-30 times (depending on the nature of the polycon densation process) when the temperature of this process increases from 400 to 1000 K.