Abstract: A method for manufacturing a semiconductor device includes: forming a patterned hard mask on a patterned structure disposed on a substrate, such that a hard mask portion of the patterned hard mask is disposed on a fin portion of the patterned structure; and laterally trimming the hard mask portion by a lateral etching process. The lateral etching process includes a radical etching process and a chemical etching process. Alternatively, the lateral etching process includes a radical etching process, a plasma etching process, or a combination thereof, and a cleaning process.

Abstract: A method for manufacturing a semiconductor device includes: forming a feature in a dielectric layer disposed on a semiconductor substrate, the dielectric layer including silicon oxide, the feature extending downwardly from a top surface of the dielectric layer and including silicon, a nitride compound, a low-k dielectric material other than silicon oxide, or combinations thereof; and selectively etching the dielectric layer using an etchant composition to form a trench extending downwardly from the top surface of the dielectric layer, the etchant composition including a hydrogen halide and a nitrogen-containing compound represented by Formula (A), wherein R1, R2, R3 are each independently hydrogen, methyl, or ethyl.

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.