Synthesis of Zn1-xMnxO Crystals by Means of Solution Deposition Method and Its Characterization

• Main Author: Firmansyah, Ardian
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/32280
• Institution: Institut Teknologi Bandung

Semiconductor is a material that play an important role in technology development, especially in electronic devices. ZnO is II–IV semiconductor material has very favorable prospects because it has a wide band gap energy of 3.3 eV and the presence of transition metals dopant can change the structural, electrical, magnetic, and optical properties of ZnO crystals. Synthesis of Zn1-xMnxO crystals by means of solution deposition method using Zn(NO3)2 100 mM as a Zn2+ source, hexamethylenetetramine 100 mM as a base, and Mn(NO3)2 as a dopant are grown on glass substrates by using external electric field as high as 2,5 kV/cm. The results of XRD and SEM characterization show that dominant crystals growth along c axis, the addition of Mn dopant causes diffraction peaks shifted to the lower 2? values. This shifting is due to the difference in ionic radius of Mn2+ (0.83Å) and Zn2+ (0.74 Å) which suggests that the Mn ions incorporated into the ZnO crystals lattice. The decrease of growth along c-axis indicates the reduction of Zn1-xMnxO crystallinity. Meanwhile, the addition of Mn dopant does not change the wurtzite structure of ZnO crystals and its lattice diameter are likely to increase. The presence of an external electrical field causes the increasing of the growth orientation uniformity in (002) plane, but the diameter of Zn1-xMnxO crystals lattice decreased. Whereas photoluminescence spectrum (PL) show an increase of the PL peaks intensity in UV region and a decrease in the intensity of the blue–green region (420–500 nm) with increasing of the Mn dopant concentrations, thus the quantity of crystals defects is reduced. Meanwhile, the variation of the external electrical field causes increasing the intensity of the PL peak in blue–green region corresponding to oxygen vacancy or Zn interstitials.