Abstract: A semiconductor device and a method for forming the semiconductor device are provided. The method includes providing a layer to-be-etched including first regions and second regions. A second region includes a second trench region. The method also includes forming a first mask layer over the first and second regions, and forming first trenches discretely in the first mask layer in the first regions. Moreover, the method includes forming a divided doped layer, and implanting dopant ions into the first mask layer disposed outside the second trench region. In addition, the method includes forming a mask sidewall spacer on a sidewall of a first trench after forming the divided doped layer and implanting the dopant ions into the first mask layer disposed outside the second trench region. Further, the method includes forming a second trench in the first mask layer in the second region.

Abstract: A method for fabricating a semiconductor device includes providing a to-be-etched layer, including alternately arranged first regions and second regions along a first direction. Each second region includes a trench region. The method includes forming a first mask layer on the to-be-etched layer; forming a doped separation layer in the first mask layer on the second region of the to-be-etched layer to divide the first mask layer along a second direction perpendicular to the first direction; forming a first trench in the first mask layer on the first region; forming a separation filling layer to divide the first trench along the second direction; implanting doping ions into the first mask layer outside of the trench region; and removing the first mask layer formed in the trench region on both sides of the doped separation layer to form a second trench that is divided into portions along the second direction.

Abstract: A semiconductor device and a method for forming the semiconductor device are provided. The method includes providing a layer to-be-etched including a first sub-trench region and a second sub-trench region. The method also includes forming a first mask layer over the layer to-be-etched and a second mask layer over the first mask layer, and forming a first sub-trench disposed over the first sub-trench region in the second mask layer. In addition, the method includes forming a first divided trench in the first mask layer and forming a second sub-trench disposed over the second sub-trench region in the second mask layer. Further, the method includes forming a first divided filling layer in the first divided trench, and forming a first middle trench in the first mask layer. The first divided filling layer divides the first middle trench in a second direction.