EMMANUEL COLL BOSTON MASS ORIENTAL SCIENCE RESEARCH LIBRARY
The relationship between growth temperature and the polytypes of SiC crystals has been studied experimentally at 2200 degrees C to 2600 degrees C under conditions of low supersaturation. The results are summarized as follows 1 In the present experiment, excluding one example in which the 4 H-type was involved, the structure of all crystals consisted of the 6 H-, 15 R- and other long c-period types exceeding 21. Of the elemental structures of SiC, 2 H, 3 C, 4 H, 15 R, 6 H, and 21 R, only 6 H and 15 R were found. 2 In the range of 2200 degrees C - 2600 degrees C, 6 H and 15 R have the most thermal stability among the structures considered as elemental. However, the effect of impurity in the crystal and the shift from stoichiometry were neglected. 3 The relative amount of 15 R increased with decreasing temperature while 6 H showed the opposite tendency. Author
Trans. of Yogyo Kyokaishi (Japan) v76 n9 p313-319 1968.