Abstract: The present disclosure describes a semiconductor device with substantially uniform gate regions and a method for forming the same. The method includes forming a fin structure on a substrate, the fin structure including one or more nanostructures. The method further includes removing a portion of the fin structure to expose an end of the one or more nanostructures and etching the end of the one or more nanostructures with one or more etching cycles. Each etching cycle includes purging the fin structure with hydrogen fluoride (HF), etching the end of the one or more nanostructures with a gas mixture of fluorine (F2) and HF, and removing an exhaust gas mixture including an etching byproduct. The method further includes forming an inner spacer in the etched end of the one or more nanostructures.