Manufacturing method of high-density shield gate groove type field effect transistor device

Abstract

The invention discloses a manufacturing method of a high-density shield gate groove type field effect transistor device, belongs to the field of power semiconductor devices, and is used for solving the problem that the cell size cannot be further reduced by the existing field effect transistor manufacturing method, and the method comprises the following steps: forming a first conductive epitaxial layer and a groove on a substrate; forming a trench insulating layer and a shield gate electrode in the groove; forming an inter-electrode isolation layer on the upper surface of the shield gate electrode; forming a gate oxide layer on the side wall of the groove; filling a gate electrode material and etching back to form a gate electrode; forming a thermal oxide layer above the gate electrode, and forming a first dielectric layer on the surface of the semiconductor; performing electric type ion implantation; forming a second dielectric layer, and forming a hard mask after back etching; etching the semiconductor to form a contact hole; forming a second heavily doped conductive type doped contact region; and forming upper surface metal to form the device. According to the manufacturing process flow of the high-density shield gate groove type field effect transistor device, the cellular size of the device is further reduced, and the on-resistance of the device is reduced.

Description

technical field [0001] The invention belongs to the field of power semiconductor devices, and in particular relates to a method for manufacturing a high-density shielded gate trench type field effect transistor device. Background technique [0002] The related technical background of the existing shielded gate trench field effect transistor will be described below. It should be pointed out that the corresponding positional words described in this document are such as "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "vertical " is the relative position corresponding to the reference illustration. The fixed direction is not limited in specific implementation. It should be pointed out that the devices in the drawings are not necessarily drawn to a specific scale. The straight line shown by the boundary of the doped region and the trench in the drawings, as well as the sharp angle formed by the boundary, are generally not straight lines and precise an...

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Problems solved by technology

[0008] In view of the problems of the existing shielded gate trench type field effect transistor devices mentioned above, it is necessary to propose a manufacturing method of a high density shielded gate trench type field effect transistor device

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