Semiconductor cell structure and power semiconductor device

A semiconductor cell structure, at least comprising:

• a highly-doped semiconductor material region (101);
• an epitaxial layer (102) formed on the highly-doped semiconductor material region (101);
• an active device region (105) formed on the epitaxial layer (102);
• the epitaxial layer (102) is provided with a deep groove (109), the deep groove (109) vertically extends into the highly-doped semiconductor material region (101), a dielectric insulating layer (103) is formed on a side wall inside the deep groove (109), the deep groove (109) is filled with a semi-insulating material (104);
• an electrode (106) in contact with the semi-insulating material (104) is formed above the semi-insulating material (104), and a bottom portion of the semi-insulating material (104) is in contact with the highly-doped semiconductor material region (101);
• wherein, the highly-doped semiconductor material region 101 is N+ type, the epitaxial layer 102 is N− type;
• when the highly-doped semiconductor material region 101 is P+ type, the epitaxial layer 102 is P− type,
• wherein, the bottom portion of the semi-insulating material (104) and a bottom portion of the dielectric insulating layer (103) vertically extend into the highly doped semiconductor material region (101) at a same depth of h;
• wherein, a thickness t of the dielectric insulating layer 103 is in a sublinear relationship with the depth h.