Preparation method of semiconductor structure and semiconductor structure

The invention relates to a preparation method of a semiconductor structure and the semiconductor structure. The preparation method of the semiconductor structure comprises the steps of forming an epitaxial layer; forming a fillet groove in the epitaxial layer; forming a first dielectric layer at the bottom of the fillet groove; a second dielectric layer is formed on the surface of the first dielectric layer and the side wall of the rounded groove, a conductive layer is formed in the rounded groove, and the conductive layer is located on the surface of the second dielectric layer. The fillet groove is formed in the epitaxial layer, accumulation of an electric field at the bottom of the groove and superposition of the first dielectric layer and the second dielectric layer can be reduced, an oxide layer with the thickened bottom can be obtained, the voltage endurance capability of the gate oxide layer is improved, and the semiconductor structure is better protected. 本申请涉及一种半导体结构的制备方法及半导体结构。半导体结构的制备方法，包括：形成外延层；于所