2X10(6) CM(2) VS ELECTRON-MOBILITY BY METALORGANIC CHEMICAL-VAPOR-DEPOSITION WITH TERTIARYBUTYLARSINE/

We demonstrate the metalorganic chemical vapor deposition (MOCVD) grow th of two-dimensional electron gases (2DEGs) with electron mobilities up to 2.0 X 10(6) cm(2)/V s at 0.3 K. These are the highest mobilities to date for MOCVD materials, and were achieved using a safer replacem ent precursor for arsine, tertiarybutylarsine (TBA). For structures gr own using arsine, we obtained a maximum mobility of 1.0 x 10(6) cm(2)/ V s, which although comparable to the best by MOCVD to date, is half t hat obtained using TBA. Our studies on thick GaAs and AlGaAs layers in dicate that the use of TBA in place of arsine reduces both the carbon and donor impurity concentrations. Thus, TBA is not only a safe altern ative to arsine, but also produces significantly purer films. (C) 1996 American Institute of Physics.