p -type conduction in wide-gap Zn1−xMgxO films grown by ultrasonic spray pyrolysis

p -type Zn1−xMgxO 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 Zn1−xMgxO film shows a low resistivity of 6.4×10−2Ωcm, high mobility of 11.7cm2∕Vs and high carrier concentration of 8.31×1018cm−3 at room temperature. Furthermore, the optical absorption edge and photoluminescence (PL) peak of p-type Zn1−xMgxO film shift to a shorter wavelength of 356nm 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 Zn1−xMgxO film based on pure ZnO film, perhaps owing to the variations in the effectiveness of Mg incorporation in the p-type Zn1−xMgxO film and in the Zn1−xMgxO film.