p-type conduction in wide-gap Zn_(1-x)Mg_xO films grown by ultrasonic spray pyrolysis

摘要

p-type Zn_(1-x)Mg_xO films doped with N and Al have been deposited by means of introducing Mg into p-type N- and Al-doped ZnO films using ultrasonic spray pyrolysis (USP) method. The structure of the films is confirmed by x-ray diffraction. Hall-effect measurements indicate that the p-type Zn_(1-x)Mg_xO film shows a low resistivity of 6.4 x 10~(-2) Ω cm, high mobility of 11.7 cm~2/V s and high carrier concentration of 8.31 x 10~(18) cm~(-3) at room temperature. Furthermore, the optical absorption edge and photoluminescence (PL) peak of p-type Zn_(1-x)Mg_xO film shift to a shorter wavelength of 356 nm while maintaining excellent electrical performances. The blueshift extent of the film based on p-type ZnO film was not as distinct as compared to that of Zn_(1-x)Mg_xO film based on pure ZnO film, perhaps owing to the variations in the effectiveness of Mg incorporation in the p-type Zn_(1-x)Mg_xO film and in the Zn_(1-x)Mg_xO film.