ISSN:
1432-0630
Keywords:
68.55.+b
;
72.80.Ey
;
72.20.Fr
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Abstract The incorporation of Sn into LPE GaAs was studied as a function of the atomic fractionx Sn l of Sn in the liquid (1.6×10−4≤x Sn l ≤0.54), the growth temperatureT K and the cooling rate α. The diffusion coefficient of As in Ga for moderate Sn-doping was deduced from the growth velocities to beD As (760° C)=(3.3±1.0)×10−5 cm2/s. The epitaxial layers were analyzed after van der Pauw with special emphasis on the sources of experimental error. With the aid of current mobility theories the concentrations of the ionized donors and acceptors were derived. From their dependence onx Sn l , on α and onT K combined with the Schottky-barrier model of Sn incorporation it can be concluded that the melt and the growing crystal surface were in thermal equilibrium. The diffusion coefficient of Sn in GaAs is about 8×10−14 cm2/s at 760° C. The distribution coefficient for Sn increases from 4.4×10−5 to 12.3×10−5 in the temperature range from 690 to 800° C. The total Sn incorporationx Sn s was measured using the atomic absorption spectroscopy for the first time down tox Sn s =1017/cm3. From these data it can be concluded that up tox Sn l =0.54 the dopant Sn is incorporated as donor and as acceptor only and that within the experimental scatter there is no indication of incorporation as a neutral species.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00885032
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