Some properties of metal organic chemical vapor deposited (MOCVD) manganese nitride thin films (MnxNy) obtained using a single precursor of Tetraamminebis-(hexamethylenetetrammine) manganese (II) chloride [Mn (HMTA)2(NH3)4] Cl2

Abstract

A single solid source precursor, tetraamminebis-(hexamethylenetetrammine) Manganese (II) Chloride [Mn (HMTA)2(NH3)4] Cl2 was prepared and thin films of manganese nitride MnxNy were grown on soda-lime glass substrates at varied temperature using Metal Organic Chemical Vapor deposition (MOCVD) technique. The Energy Dispersive X-ray (EDX) spectra showcased the thin film constituent's elements as Mn and N in weight ratios which further confirmed absolute stoichiometry. The Fourier Transform Infra-Red (FTIR) spectrometry carried out on the precursors revealed the presence of functional groups between 1600 and 3200 cm−1 in the precursors, and ligands were mostly removed by pyrolysis process of the MOCVD at a temperature range of 300–340 °C. Due to the thermal deposition technique employed, FTIR spectrographs of MnN thin films exhibit coalescences between grains and a clear bond disintegration. Structural characterization using X-ray diffraction (XRD) revealed that the synthesized MnN thin film possesses a simple cubic structure with crystallite sizes estimated by employing Scherer's formula and Hall–Williamson plots. The scanning electron microscopy (SEM) showed columnar pattern and mesopores with the substrate covered by smaller, spherical grain particles having an estimated size of 3–4 nm, and large, structured particles with an estimated size of 10.0–20.0 nm placed on top of the smaller grain size particles. The indirect optical bandgap value of the MnN thin film was confirmed by optical absorbance analysis to be 2.75 eV and 3.0 eV at temperatures of 300 and 340 °C, respectively.