Abstract: A method of manufacturing a semiconductor structure includes the following operations. A buffer layer is formed over a substrate. A first top hard mask is formed on the buffer layer, in which the first top hard mask has a first trench to expose a first portion of the buffer layer. A spacer layer is formed to cover a sidewall of the first trench and an upper surface of the first top hard mask and the first portion of the buffer layer to form a second trench over the first portion. The top portion and the bottom portion are etched to form a thinned top portion and a thinned bottom portion. A second top hard mask is formed in the second trench. The thinned top portion and the vertical portion of the spacer layer are removed.

Abstract: A method of forming fine line patterns of semiconductor devices includes: forming a plurality of linear core structures on at least one hard mask layer disposed on a target layer; forming first spacers on sidewalls of the linear core structures; removing the linear core structures; forming second spacers on sidewalls of the first spacers; etching exposed portions of the hard mask layer exposed by the first spacers and the second spacers; and removing the first spacers and the second spacers.

Abstract: The present disclosure provides a method for preparing semiconductor structures. The method includes the following steps: A substrate is provided. A plurality of first core features spaced apart from each other is formed over the substrate. A spacer layer is formed over the first core features, and the spacer layer is formed to cover sidewalls and top surfaces of each first core feature. A plurality of second core features is formed over the substrate, and portions of the spacer layer are exposed through the second core features. A densification treatment is performed on the second core features, and the spacer layer is removed to form a plurality of openings between the first core features and the second core features.