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In this work, a 6 GHz TESLA-shaped cavity was split into two halves along its axis to enable an experimental study following a process flow of half-cell fabrication, surface treatment, film deposition, assembly, and testing. The half-cells were fabricated from high-purity oxygen-free copper by precision machining, and subjected to mechanical polishing followed by SUBU chemical etching prior to film deposition. Nb₃Sn films were deposited by magnetron co-sputtering at a substrate temperature of approximately 750 °C, yielding a film thickness of about 2 μm, with a Nb interlayer employed as a buffer. The films were subsequently annealed in situ at 750 °C for 12 h. The resulting Nb₃Sn films exhibited critical temperatures (Tc) above 17.3 K at the tube, cell, and equator regions. SEM and FIB characterization revealed that the films were uniform and dense, with tight and continuous interfaces. The two half-cells were vacuum-sealed using an indium wire seal, which demonstrated good sealing performance during liquid-nitrogen cooling tests, with no leakage detected after two thermal cycles of warming and cooling.