Oxygen Precipitation Nonuniformity for Thermal History Around 723K During Cz Crystal Growth

Autor: I. Fusegawa, Hirotoshi Yamagishi
Rok vydání: 1992
Předmět:
Zdroj: MRS Proceedings. 262
ISSN: 1946-4274
0272-9172
DOI: 10.1557/proc-262-63
Popis: We investigated phenomena of oxygen precipitation nonuni-formity along crystal growth axis due to different thermal histories during CZ crystal growth. The oxygen precipitation process employed in this paper was two-step thermal treatments consisting of the first annealing in nitrogen ambient at 1073K for 4 hrs and the second annealing in dry oxygen ambient at 1273K for 16 hrs. The amount of the oxygen precipitation at the shoulder of a silicon single crystal was higher than the one at the tail end. We found this nonuniform distribution profile was due to the thermal history around 723K during crystal growth. Such an nonuniformity could be improved remarkably by adding a preannealing in dry oxygen ambient at 723K for 2 hrs before the two-step thermal treatment.
Databáze: OpenAIRE