1：Experimental Design and Method Selection:

Graphene films were grown onto two different thickness levels of SiO2/Si substrates using pulsed laser deposition (PLD) with the help of Ni film from highly ordered pyrolytic graphite. The influence of buffer layers of SiO2 thickness on the PLD growth, quality, thickness, and crystallite size of graphene film was studied in terms of substrate temperatures.

2：Sample Selection and Data Sources:

Two different types of SiO2/Si substrates were used: commercially available SiO2 (100 nm)/Si and thermally grown 400 nm thick SiO2 layer over Si. Approximately 250 nm thick Ni film was sputtered onto these substrates.

3：List of Experimental Equipment and Materials:

PLD chamber (Excel Instruments, India), Nd:YAG laser (532 nm wavelength, pulse width 8 ns), Raman spectroscopy (Reinshaw microscope), FESEM (Carl, Zeiss), XPS (PHI 5000 Versa Probe III).

4：Experimental Procedures and Operational Workflow:

Ni deposition was performed by dc sputtering. Graphene growth was carried out for 100 s using 532 nm wavelength of Nd:YAG laser with pulse width 8 ns and a pulse repetition rate of 10 Hz. The substrate temperature was varied from 700 °C to 800 °C.

5：Data Analysis Methods:

Raman spectra were analyzed to determine the quality, growth, number of graphene layers, defect density, and crystallite size of graphene films. XPS was used to investigate the C-C sp2 bonding, and SEM was used to observe the microstructure of graphene samples.