High-voltage element and manufacturing method thereof

The invention provides a high-voltage element and a manufacturing method thereof. The high-voltage element comprises a semiconductor layer, a well region, a substrate region, a grid electrode, a source electrode and a drain electrode. The base region has a second conductivity type, is formed in the semiconductor layer and is connected to the well region in the channel direction. The grid electrode is formed on the semiconductor layer, and a part of the substrate region is located under the grid electrode and connected to the grid electrode so as to provide a reversal region of the high-voltage element in conduction operation. The source electrode is located in the substrate region, the drain electrode is located in the well region away from the substrate region, and part of the well region is located between the substrate region and the drain electrode to separate the substrate region from the drain electrode. A first concentration peak region of the impurity doping profile of the base region is located direc