| 摘要 |
A semiconductor device and its forming method are provided to improve a process margin in an isolation layer forming process by forming an isolation layer using a double STI process. A first trench with a negative slope is formed on a semiconductor substrate(100). A second trench is formed under the first trench. The second trench has a positive slope. The width of the second trench is smaller than that of the first trench. An isolation layer(130) is filled in the first and second trenches. At this time, an active region(120) is defined by the isolation layer. A gate(200) is formed on the active region of the resultant structure. A recess gate is used as the gate, wherein the recess gate includes a recess region overlapped with the active region.
|
