Method for forming insulating groove in substrate and semiconductor device

Abstract

The invention provides a method for forming an insulating groove in a substrate and a semiconductor device. The method comprises the steps as follows: an insulating layer is formed in the region, in which an insulating groove is to be formed, on the surface of a substrate, wherein the insulating layer can be taken as the bottom of the insulating groove, the specific thickness can be correspondingly adjusted according to the device type and the operating requirements, forming of the insulating layer on the surface of the substrate is relatively easy to implement, and the thickness and the region range are relatively easy to control; an epitaxial layer is formed on the substrate, and the structure of the epitaxial layer can be determined according to the type of the semiconductor device; andan opening is formed in the epitaxial layer to expose the insulating layer, thereby forming the insulating groove. Compared with the prior art, the method has the advantages that control on the thickness of the bottom of the insulating layer at the bottom of the groove and improvement of electric field distribution can be implemented, additional equipment or process is not needed for implementation, and the implementation procedure and the implementation process are simple.

Description

technical field [0001] The invention relates to the technical field of chip manufacturing, in particular to a method for forming an insulating trench on a substrate and a semiconductor device. Background technique [0002] The importance of power semiconductor devices has become increasingly prominent under the continuous and rapid growth of energy demand, and they are widely used in switching power supplies, automotive electronics, new energy, power transmission and transformation, rail transit, metallurgy and chemical industries. [0003] Power semiconductor devices are usually used as switches, and their on-resistance and breakdown voltage are two key parameters. Reducing the on-resistance can reduce the dynamic and static loss of the device and increase the switching speed. Therefore, generally, the trench gate structure is used to reduce the on-resistance of the device, of which figure 1 An exemplary structural diagram of a trench gate semiconductor is shown. The proce...

AI Technical Summary

Problems solved by technology

In the technical solution adopted in the Chinese patent application CN106409898A, although the post-implantation of high-energy oxygen ions to thicken the bottom oxide layer can effectively reduce the peak value of the electric field at the corner of the trench, however, injecting high-energy oxygen ions into the lower part of the N-type region requires Implantation by special equipment (high-energy oxygen ion implantation equipment) increases the production cost of semiconductor devices with insulating trenches, making the process more complicated and high in production cost

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