A method of vapor depositing a silane chemical onto a wire grid polarizer can include introducing a silane chemical and water into a chamber where the wire grid polarizer is located. The silane chemical and the water can be in a gaseous phase in the chamber. The silane chemical and the water can be maintained simultaneously in the gaseous phase in the chamber for period of time. The silane chemical and the water can react to form a (R1)2Si(OH)2 molecule, where each R1 is independently any chemical element or group. A silane coating can be formed on the wire grid polarizer from a chemical reaction of the (R1)2Si(OH)2 molecule with the wire grid polarizer and with other (R1)2Si(OH)2 molecules. The silane coating can be relatively thick and multi-layer. A thicker or multi-layer silane coating can have improved high temperature resistance relative to a thinner or mono-layer silane coating.