Anisotropy in the doping characteristics of dimethylcadmium in GaAs grown by MOVPE on (100) GaAs

• Published in: Journal of crystal growth Vol. 99; no. 1; pp. 329 - 332
• Main Authors: Matsumoto, Koh, Hidaka, Jun-ichi, Uchida, Kazuo
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 1990; Elsevier
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Physics; Solid surfaces and solid-solid interfaces; Surface and interface dynamics and vibrations; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/0022-0248(90)90538-V

GaAs layers have been grown by MOVPE on nominal and vicinal (100) GaAs substrates. The effects of doping using dimethylcadmium have been studied as a function of misorientation of the substrate. The hole concentration N A is found to increase exponentially with the DMCd flow rate for the samples grown at 720°C on (100)±0.5°, (100) 2° off towards (111)B and (110) planes, but it increases linearly for the samples grown at 720°C on (100) 2° off towards the (111)A plane. N A for the layers grown at 680°C is, however, proportional to the DMCd flow rate for all the substrates. These results are explained in terms of step pinning due to kink poisoning by the impurity atoms, and the resultant increase in the supersaturation for two-dimensional growth and impurity-induced nucleation, taking account of the anisotropy in the steps on (100) GaAs.