1：Experimental Design and Method Selection:

The study used pulsed laser deposition (PLD) with in situ reflection high-energy electron diffraction (RHEED) monitoring to grow epitaxial Si-doped HfO2 films on N-type SrTiO3 (NSTO) substrates. Various characterization techniques including XRD, HRTEM, PFM, and XAS were employed to analyze structural and ferroelectric properties.

2：Sample Selection and Data Sources:

Epitaxial Si-doped HfO2 films with 4.4% mole Si doping and thicknesses ranging from 1.5 to 15 nm were grown on differently oriented NSTO substrates ([001]P, [110]P, [111]P). Data were sourced from experimental measurements and comparisons with standard samples like HfO2 powder.

3：4% mole Si doping and thicknesses ranging from 5 to 15 nm were grown on differently oriented NSTO substrates ([001]P, [110]P, [111]P). Data were sourced from experimental measurements and comparisons with standard samples like HfO2 powder. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: PLD chamber with KrF excimer laser, RHEED facility, high-resolution XRD (Rigaku SmartLab), TEM instruments (Tecnai G2 F20 and FEI TITAN G2), PFM (MFP-3D Asylum Research), AFM with silicon tips, ferroelectric tester (Radiant Precision Premier II), XAS beamlines at NSRRC, and substrates (NSTO). Materials included Si-doped HfO2 targets and NSTO substrates.

4：Experimental Procedures and Operational Workflow:

Films were deposited at 700°C and 100 mTorr oxygen pressure with specific laser fluence and repetition rates. Post-growth cooling was at 10°C/min. Structural analysis via XRD and TEM, ferroelectric property measurements via PFM and P-E loops, and electronic structure analysis via XAS were conducted step by step.

5：Data Analysis Methods:

Data were analyzed using FFT for TEM images, statistical analysis for PFM and P-E measurements, and spectral analysis for XAS to interpret crystal field splitting and electronic structure changes.