Specific features of the dislocation structure of germanium in the system germanium–pyrolitic silica film

Abstract

The dislocation structure of germanium covered by a SiO2 pyrolitic film has been studied by X‐ray topography. The dislocations gliding in the Ge bulk are accompanied by the formation of steps on the optically smooth interface GeSiO2. Dislocations and steps are shown to be connected with a bending of the GeSiO2 system which is due to the densification of the film during its synthesis. In the germanium bulk a neutral surface N arises with dislocations accumulated near this surface. The interaction of dislocations with equal sign results in their symmetric distribution respective to N, if they lie in the same slip plane, while those ones lying in the intersecting slip planes interact with the formation of L‐type prismatic dislocations. A study of dislocation interaction near N gives estimates of the structural stresses in the film and in germanium.

Dislocations and stresses in a crystal with an island film

“…4c. I t is seen that, calculations by (l), ( 7 ) , and (2) to ( 7 ) give close resnlts with comparable accuracy. The mean level of z , , a t the edges of islands is 6 x lo6 dyn/cni2.…”

“…The further account of z , , is possible only in centres of islands and uncoated areas using ('i), as well as a t the film edges for which far froin the short sides a = z,,(ki f ik) and (6) holds, though p and y are not zero. z , , estimated by (l), ( 7 ) , and ( l ) , (6) are shown in Fig. 4c.…”

Some features of generation of misfit dislocations in Si during B diffusion from doped oxide

“…The stress in the substrate during the high temperature treatment was estimated from the dislocation configuration [3]. On the other hand, the curvature of the crystals was measured by a double crystal goniometer ((321) cut Si monochromator with asymmetric 422 reflection of CuKa, radiation).…”

“…MDs as well as straight dislocations lying in the neutral surface can interact to form L-shaped dislocations [3]. The mentioned theoretical study is not generalized, however, for systems with multilayer films.…”

“…Crystals with diffused layers on their surfaces are equivalent, from the point of view of generation of MDs, to heteroepitaxial structures. I n heterostructures with amorphous layers steps are generated on the interface which are equivalent to MDs [3] and it was shown [l] that the concept of the misfit parameter can be generalized for such structures, too.…”