Metalorganic chemical vapor deposition of highly conductive Al0.65Ga0.35N films

Highly conductive Al0.65Ga0.35N films were fabricated using indium-silicon codoping and a low growth temperature of 920 degreesC in the metalorganic chemical vapor deposition process. The Al0.65Ga0.35N:(Si, In) layers exhibited an n-type carrier density as high as 2.5x10(19) cm(-3) with an electron mobility of 22 cm(2)/V s, corresponding to a resistivity of 1.1x10(-4) Omega cm. Significantly higher resistivity values were measured for AlxGa1-xN: Si doped films with xgreater than or equal to0.49 deposited at 1150degreesC without indium, e.g., the Al0.62Ga0.38N: Si samples exhibited a maximum carrier concentration of 1.3x10(17) cm(-3) and a resistivity of 6.2x10(-2) Omega cm. The electrical properties of the films are discussed in relation to the chemical concentrations of silicon and residual impurities in the films. (C) 2003 American Institute of Physics.