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Purpose: This study aims to investigate the effect of temperature applied at the initial deposition of Aluminium Nitride (AlN) thin-film on a silicon substrate by high-power impulse magnetron sputtering (HiPIMS) technique. Design/methodology/approach: HiPIMS system was used to deposit AlN thin film at a low output power of 200 W. The ramping temperature was introduced to substrate from room temperature to maximum 100°Cat the initial deposition of thin-film, and the result was compared to thin-film sputtered with no additional heat. For the heat assistance AlN deposition, the substrate was let to cool down to room temperature for the remaining deposition time. The thin-films were characterized by X-ray diffraction (XRD) and atomic force microscope (AFM) while the MIS Schottky diode characteristic investigated through current-voltage response by a two-point probe method. Findings: The XRD pattern shows significant improvement of the strong peak of the c-axis (002) preferred orientation of the AlN thin-film. The peak was observed narrowed with temperature assisted where FWHM calculated at 0.35° compared to FWHM of AlN thin film deposited at room temperature at around 0.59°. The degree of crystallinity of bulk thin film was improved by 28% with temperature assisted. The AFM images show significant improvement as low surface roughness achieved at around 0.7 nm for temperature assisted sample compares to 3 nm with no heat applied. Originality/value: The small amount of heat introduced to the substrate has significantly improved the growth of the c-axis AlN thin film, and this method is favorable in the deposition of the high-quality thin film at the low-temperature process. [ABSTRACT FROM AUTHOR]

Aluminum nitride (AlN) and gallium nitride (GaN) thin films were grown on silicon (Si) substrates using the conventional RF magnetron sputtering plasma deposition system. The growth rate of GaN increased as the deposition power of GaN increased. There was no crystalline peak of GaN observed, since there was no additional substrate heating. However, a highly crystalline AlN was observed and its peak orientations of (001) and (002) changed with the growth of GaN films at various RF discharge powers. The film's composition analysis using energy-dispersive X-ray spectroscopy (EDS) confirmed the existence of Ga and N in the thin films. AFM results showed that the surface roughness (Ra) of the GaN/AlN thin films increased with increased RF discharge power. FESEM images showed a good agreement with the AFM results, since the grain size increased as the surface roughness increased. The electrical properties studied using Hall effect showed that a low discharge power of GaN led to low resistance, high carrier concentration and low Hall mobility, which are good for devices in optoelectronic applications. [ABSTRACT FROM AUTHOR]