1results about How to "Reduce step height" patented technology

This invention provides a method for manufacturing a semiconductor device. Before the active region manufacturing process, trench etching is performed on the substrate region to be fabricated as a high-voltage transistor to form at least a first depth adjustment trench located outside the gate oxide region of the high-voltage transistor. A first drift region is then formed by ion implantation. This solves the problem of incomplete corner implantation caused by the rounded exposure of photoresist corners in existing LDD processes. Furthermore, the depth of the first depth adjustment trench increases the bottom depth of the shallow trench isolation structure used to isolate the source / drain regions and channel regions of the high-voltage transistor, increasing the charge path of the high-voltage transistor and its breakdown voltage. Further, by simultaneously forming a gate oxide trench for fabricating a thick gate oxide layer with the first depth adjustment trench, the step height between the high-voltage transistor and other components is reduced, thereby reducing the load effect and defects in subsequent processes and improving the performance of the high-voltage transistor.