Carefully toss zucchini, vinegar, and oil in a medium bowl, tossing to coat well. Let marinate for about 10 minutes.
Line 2 baking sheets with parchment paper, and place zucchini slices in a single layer.
Season lightly with salt.
Bake at 200°F for 2 to 2.5 hours, or until chips are crispy and lightly golden. Flip chips after the first hour. Remove from oven; cool completely.