摘要
This study presents a comparative analysis of silicon dioxide (SiO2) thin films deposited by Radio Frequency (RF) magnetron sputtering and reactive High-Power Impulse Magnetron Sputtering (HiPIMS). The influence of sputtering power and the HiPIMS pulse-on time (10 - 40 & micro;s) on the deposition characteristics, microstructural evolution, and optical properties was investigated. Contrary to the typical rate reduction observed in metallic HiPIMS, reactive HiPIMS demonstrates a higher deposition rate than RF sputtering at equivalent average powers, attributed to the effective suppression of target poisoning. Microstructural analysis reveals that films deposited by RF sputtering and long-pulse (40 & micro;s) HiPIMS exhibit porous microstructures with rough surfaces. In contrast, reducing the pulse-on time to 10 & micro;s induces a transition to an atomically smooth (Rq approximate to 1.1 nm) and dense morphology. This surface planarization is linked to the substantial kinetic energy transferred to sputtered species by the high peak power density of short pulses, which enhances adatom mobility. Spectroscopic ellipsometry was employed to determine the SiO2 thin films optical constants of the SiO2 thin films. The results confirmed that the HiPIMS 1000W, 10 & micro;s condition yields a refractive index (n approximate to 1.46 at lambda = 632.8 nm), consistent with stoichiometric SiO2 and low surface roughness Overall, short-pulse reactive HiPIMS is identified as a superior technique for fabricating high-performance optical coatings, combining high deposition efficiency with superior film quality.