| Abstract: | The initial stage of small gap heteroepitaxial growth of magnesium-manganese ferrite films during chemical gas transportation reactions on orientation (100) magnesium oxide substrate was studied. Film growth would begin with origination of parallely oriented three-dimensional nuclei, their shapes at lower (1170 K) and at appear (1420 K) film synthesis temperature limits being different. After little islands had grown together and continuous layer formed the secondary nuclei would appear, their shapes resembling cut-up pyramids. Continuous layer minimum thickness was 0.15 μm. The growing together of little islands results in film block structure. Block sizes could be as big as 300–400 μm if films grow at the speed of 2 μm/min, the density of islands being 106 cm−2. Linear density of unconformity dislocations at film-substrate boundary would be (3.7 ÷ 7.4) 103 cm−1. It would depend on magnesium content for a film. Elastic stresses in films would come to 7 · 108 ÷ 3 · 109 dyne/cm2. X-ray topography pictures of block structures and of accumulations of admixtures at block boundaries are presented. |
