Primitive cell structure of power device and forming method of primitive cell structure

The invention provides a primitive cell structure of a power device and a forming method of the primitive cell structure of the power device, and the primitive cell structure of the power device comprises a shielding gate, a control gate and an isolation oxide layer, wherein the control gate and the isolation oxide layer wrap the top of the shielding gate from outside to inside, and the bottom surfaces of the control gate and the isolation oxide layer are aligned. According to the invention, the problem that the surface of the field oxide layer is uneven after being etched by the acid liquor in the prior art can be improved only by changing the process sequence without increasing the photomask cost or changing the device design, so that the morphology and the thickness of the isolation oxide layer are improved, and the problem of electric leakage between the shield gate and the isolation gate is improved. 本发明提供一种功率器件的原胞结构及其形成方法，所述功率器件的原胞结构，包括：屏蔽栅、控制栅及隔离氧化层；其中，所述控制栅及所述隔离氧化层自外向内包覆所述屏蔽栅的顶部且底面之间相对齐。本发明仅通过改变工艺顺序，无