1：Experimental Design and Method Selection:

A near-field assisted EHD jet spray system was developed by adding a ring-type electrode around the needle tip to control spray patterns and droplet characteristics. The method involves applying electric fields to jet and spray the ZTO solution onto substrates.

2：Sample Selection and Data Sources:

ZTO thin-films were sprayed onto silicon wafers with a 300 nm thick silicon oxide insulator. The solution was prepared by mixing tin chloride and zinc acetate dihydrate in 2-ethoxyethanol.

3：List of Experimental Equipment and Materials:

Equipment includes an EHD spray system with a ring electrode, thermal annealing oven, X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM, Joel), ellipsometer (Gartner L116D), atomic force microscope (AFM, PSIA XE-150), semiconductor parameter analyzer (Keithley 4200), and X-ray photoelectron spectrometer (XPS, Thermo VG ESCA Sigma Probe). Materials include ZTO precursor solution, silicon wafers, and aluminum for electrodes.

4：Experimental Procedures and Operational Workflow:

The NF-EHD jet was sprayed with optimized parameters (e.g., nozzle voltage 8 kV, ring voltage 5.2 kV, spray distance 45 mm, substrate temperature room temperature, spray time 60 s). Films were annealed at 400°C for one hour. Electrical and structural characterizations were performed using the listed equipment.

5：2 kV, spray distance 45 mm, substrate temperature room temperature, spray time 60 s). Films were annealed at 400°C for one hour. Electrical and structural characterizations were performed using the listed equipment. Data Analysis Methods:

5. Data Analysis Methods: Electrical properties were derived from transfer curves using saturation equations. XRD, SEM, AFM, and XPS data were analyzed to assess film morphology, crystallinity, and composition. Statistical analysis of oxygen vacancies and hydroxyl groups was done using XPS peak fitting.