Improvement of c-axis (002) AlN crystal plane by temperature assisted HiPIMS technique

Abstract

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.

Citation

Azman, Z., Nayan, N., Megat Hasnan, M.M.I., Othman, N., Bakri, A.S., Abu Bakar, A.S., Mamat, M.H. and Mohd Yusop, M.Z. (2021), "Improvement of c-axis (002) AlN crystal plane by temperature assisted HiPIMS technique", Microelectronics International, Vol. 38 No. 3, pp. 86-92. https://doi.org/10.1108/MI-02-2021-0013