Abstract: Provided is a semiconductor device including a substrate, multiple first gate structures, and a protective structure. The substrate includes a first region and a second region. The first gate structures are disposed on the substrate in the first region. The protective structure conformally covers a sidewall of one of the first gate structures adjacent to the second region. The protective structure includes a lower portion and an upper portion disposed on the lower portion. The lower portion and the upper portion have different dielectric materials. A method of forming a semiconductor device is also provided.

Abstract: The method of forming the semiconductor structure includes the following steps. First trenches and second trenches are respectively formed in a substrate of the logic region and the substrate of the array region. A dielectric liner is formed in the first trenches and second trenches. First coating blocks and second coating blocks are respectively formed in the first trenches and second trenches. A cap layer is formed on the first coating blocks and the second coating blocks. Oxide structures are formed on the cap layer. Part of the oxide structures and part of the cap layer is removed. A semiconductor layer is formed in the array region and disposed on the substrate and between the oxide structures.

Abstract: Provided is a semiconductor device including a substrate, multiple first gate structures, and a protective structure. The substrate includes a first region and a second region. The first gate structures are disposed on the substrate in the first region. The protective structure conformally covers a sidewall of one of the first gate structures adjacent to the second region. The protective structure includes a lower portion and an upper portion disposed on the lower portion. The lower portion and the upper portion have different dielectric materials. A method of forming a semiconductor device is also provided.