Semiconductor device structure and forming method thereof

The embodiment of the invention provides a semiconductor device structure and a forming method thereof. The method includes depositing a spacer layer over an isolation region between adjacent fin structures, and the spacer layer is formed on sidewalls and tops of the fin structures. The method further includes forming a mask on the spacer layer between the fin structures, and a height of the mask is substantially less than a height of the fin structures. The method further includes removing portions of the spacer layer and recessing the fin structures to form spacers and expose portions of each fin structure, the spacers including a first portion having a "U" shape disposed on the isolation region, and each fin structure portion having a top surface at a level substantially lower than a top surface of the isolation region. The method further includes removing the mask. 本公开的实施例提供半导体器件结构及其形成方法。该方法包括在相邻的鳍结构之间的隔离区域上方沉积间隔件层，并且间隔件层形成在鳍结构的侧壁和顶部上。该方法还包括在鳍结构之间的间隔件层上形成掩模，并且该掩模的高度基本上小于鳍结构的高度。该方法还包括去除间隔件层的部分并且使鳍结构凹进以形成间隔