Effects of growth conditions and substrate orientation on the properties of InSb.

摘要

Two new organometallic Sb sources, tris(dimethylamino)antimony (TDMASb), and tertiarybutyldimethylantimony (TBDMSb) are being investigated. Growth of InSb using TDMASb, or TBDMSb and TMIn was investigated at 350 to 475C using a range of V/III ratios, growth rates and pressures. Misoriented InSb substrates were also used for selected growth conditions. The growth rates of InSb using TMIn and either TDMASb or TBDMSb at temperatures (le) 425C were proportional to both the TMIn flow rate and the temperature. The surface morphology of InSb grown using either TDMASb or TBDMSb was very rough for growth temperatures (le) 425C. This may be due to the complex decomposition mechanisms involved and the presence of methyl groups on the surface. Smoother backgrounds were generally found when using off axis substrates. The details of the defects observed on the surfaces were dependent on the type of misorientation and can be related to the atomic structure of the surface steps. Both n- and p-type InSb were grown using TBDMSb or TDMASb and TMIn with mobilities up to 68,990 and 7773 cm(sup 2)/Vs, respectively, at 77 K. The mobility for InSb using either TDMASb or TBDMSb was optimized by going to lower temperatures, pressures and V/III ratios. The opposite was true for surface morphology which improved with higher temperature, pressure, and V/III ratio. The growth of high mobility InSb with smooth surfaces at T (le) 425C was not achieved with TDMASb or TBDMSb and TMIn under the conditions investigated in this work.