An igbt gate bus structure

Abstract

The invention discloses an IGBT gate bus structure, which comprises a substrate, a field oxide layer and gate polysilicon sequentially arranged along one end of the upper surface of the substrate from outside to inside, and a gap is left between the field oxide layer and the gate polysilicon; It also includes a dielectric layer, the dielectric layer covers the entire upper surface of the substrate and the upper surface of the field oxide layer and the gate polysilicon, and a gate contact hole is opened in the dielectric layer on the upper surface of the gate polysilicon; so that the upper surface of the gate polysilicon Steps and unevenness are avoided, and when the gate contact hole is etched in the dielectric layer on the upper surface of the gate polysilicon, a complete gate contact hole can be etched without being affected by the unevenness of the upper surface of the gate polysilicon.

Description

technical field [0001] The invention relates to the technical field of power semiconductor devices, in particular to an IGBT gate bus structure. Background technique [0002] IGBT (Insulated Gate Bipolar Transistor, Insulated Gate Bipolar Transistor) chip combines MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor, Metal-Oxide Semiconductor Field Effect Transistor) and BJT (Bipolar Junction Transistor, Bipolar Junction Transistor) ), has the advantages of high input impedance, low power consumption under voltage control, simple control circuit, high voltage resistance, and large current, and has been widely used in various power conversions. Among them, the gate bus of the IGBT has the function of enabling the cells of the chip to be turned on synchronously. A reasonable design of the gate bus can effectively improve the performance of the IGBT chip. [0003] figure 1 It is a traditional gate bus structure, including field oxide layer 1, gate polysilicon 2, gate met...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide an IGBT gate bus structure to solve the problem that the surface of the gate polysilicon in the prior art is uneven, and when a gate contact hole is opened in the dielectric layer above the gate polysilicon, process defects are very likely to occur.

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