Embodiments disclosed herein include methods of developing a metal oxo photoresist. In an embodiment, the method comprises providing a substrate with the metal oxo photoresist into a vacuum chamber, where the metal oxo photoresist comprises exposed regions and unexposed regions. In an embodiment, the unexposed regions comprise a higher carbon concentration than the exposed regions. The method may further comprise vaporizing a halogenating agent into the vacuum chamber, where the halogenating agent reacts with either the unexposed regions or the exposed regions to produce a volatile byproduct. In an embodiment, the method may further comprise purging the vacuum chamber.