1：Experimental Design and Method Selection:

The study involved fabricating vertical Ga2O3 diodes with W/Au and Ni/Au Schottky contacts to compare their thermal stability and electrical properties up to 500°C, using thermionic emission models and XPS for barrier height determination.

2：Sample Selection and Data Sources:

n-type β-Ga2O3 wafers from Tamura Corporation with a carrier concentration of 2 × 10^17 cm^-3 were used. Electrical measurements were conducted at temperatures from 25°C to 500°C.

3：List of Experimental Equipment and Materials:

Equipment included an HP 4156 parameter analyzer for I-V measurements, Agilent 4284A Precision LCR Meter for C-V measurements, Physical Electronics 5100LSci spectrometer for XPS, electron beam evaporator for metal deposition, and dc sputtering system for W deposition. Materials included Ti, Au, W, Ni, and Ga2O3 substrates.

4：Experimental Procedures and Operational Workflow:

Fabrication involved back ohmic contact deposition (Ti/Au), annealing, surface cleaning with HCl and ozone, Schottky contact deposition (W by sputtering and Au by E-beam evaporation), annealing at 300°C, and electrical measurements on a hot stage with 10-minute stabilization at each temperature. XPS was used before and after annealing.

5：Data Analysis Methods:

Barrier heights and ideality factors were extracted from I-V curves using the thermionic emission model. Richardson's constant and effective barrier height were determined from Arrhenius plots. XPS data were charge-corrected and analyzed for binding energy shifts.