ORIENTED AND TEXTURED GROWTH

It is known that the relative growth rates on 100 and 111 planes Vjoo/v,ii determine the crystal habit of diamond, and the appearance or disappearance of crystallographic planes in diamond films depends on the growth velocities of the corresponding planes. The facets that appear on a crystal are those for which the normal gro vth velocity is the slowest. On the basis of the simple Wullf criterionl O for crystal habit, the most stable growth planes in diamond are the octahedral 111 planes, followed by the 

Based on this mechanism. Wild et al.l l developed a two-dimensional computer program to simulate the crystal growth evolution and the surface morphology of polyerystalline films grown from square nuclei with random orientations and random positions on a substrate. The calculated - - and experimentalP lP l results show that, for the diamond films (150-400 pm in thickness) investigated under the experimental conditions, (110) is the direction of fastest growth with the film surfaee eonsisting of 111 planes. 

The degree of the (110) fiber texture improves (i.e., a preferential orientation of 110 planes develops) with increasing film thickness. However, the film texture and surface morphology are critically dependent on the growth conditions. Under conditions where 100 or both 100 and 111 planes develop, the preferred orientations different from the (110) fiber texture may form. 

In the case of the homoepitaxial or heteroepitaxially textured films of 100 orientation, the microstructure and morphology of the films are 

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