Semiconductor line feature and manufacturing method thereof

Abstract

Some embodiments of the present disclosure provide a semiconductor structure with a reduced line feature. The semiconductor structure includes a substrate, a first active region in the substrate and having a first sidewall, a second active region in the substrate and having a second sidewall, an isolation region contacting the first sidewall and the second sidewall. The above-mentioned semiconductor structure possesses a width of a top surface of the isolation region less than 50 nm and a width of a bottom surface of the isolation region more than 20 nm. Some embodiments provide a method for controlling a semiconductor line feature in a wafer, including patterning a hard mask exposing a line feature with a line width narrower than 50 nm on a wafer, forming a trench on the wafer correlated to the line feature by performing a plasma dry etch over the wafer, and filling the trench with isolation materials.