Semiconductor structure and preparation method thereof

The invention provides a semiconductor structure and a preparation method thereof. According to the method, the DTI and STI overlapped layout is utilized, the trench oxide material deposition, planarization and other process manufacturing procedures of the STI manufacturing procedure are also applied to the DTI manufacturing procedure, the thermal manufacturing procedure is reduced, the stress generated by the thermal manufacturing procedure is further reduced, interference to a device is reduced, and the performance of the device is improved. In addition, due to the process of combining the parts, the cost of the respective independent process can be reduced. Most importantly, under the new manufacturing process, the STI is arranged around the DTI, the outline of the DTI does not have a silicon base foot, and the performance of the device is further improved. 本发明提供了一种半导体结构及其制备方法。本发明利用DTI和STI重叠版图，将STI制程的沟槽氧化物材料沉积以及平坦化等工艺制程同样用于DTI制程上，减少热制程，进而减少热制程所产生的应力，以减少对于器件的干扰，提高器件性能。此外由于合并部分的制程，因此可减少各自独立制程时的成本。最重要的是，这种新制程