Fast recovery diode (FRD) device structure and manufacturing method thereof

Abstract

The invention provides a fast recovery diode (FRD) device structure and a manufacturing method thereof. An insulation layer is formed on the side wall of a trench of the FRD device structure, and the insulation layer is combined with the surface of a P-type doped region to form a combining center, so that a combining route from the P-type doped region to the insulation layer is formed, and the reverse recovery characteristic of the device is improved effectively; furthermore, due to the presence of the insulation layer on the side wall of the trench, partial combined current carriers which reach the upper surface of the P-type doped region from the P-type doped region through the combining route are shielded by the insulation layer and combined on the surface of the insulation layer, so that the emission efficiency is improved and the state voltage drop is reduced; moreover, the doping concentration at the bottom of the trench in the P-type doped region is controlled, so that the diffusion length of the current carriers is prevented from being dramatically reduced, the scattering of the current carriers and an auger combining effect are avoided, the emission efficiency of the bottom region of the trench in the P-type doped region is improved, the rising of the state voltage drop of the trench caused by doping reduction is compensated, and the forward voltage drop is improved.

Description

technical field [0001] The invention relates to a device structure and a manufacturing method in the field of integrated circuit manufacturing, in particular to an FRD structure and a manufacturing method thereof. Background technique [0002] With the continuous reduction of oil and coal reserves, and the continuous increase of human energy consumption, energy conservation has become the consensus of human beings in the 21st century. The U.S. Department of Energy estimates that two-thirds of electricity is used to drive motors. The use of IGBT and its matching FRD and other power devices can make the motor drive energy-saving by 20% to 30%. It can be expected that power devices will grow rapidly in the future. [0003] For FRD (Fast recovery diode, fast recovery diode) power devices, its reverse recovery characteristics and forward conduction voltage drop are very important. High forward conduction voltage drop means low energy conversion efficiency, and poor reverse reco...

AI Technical Summary

Problems solved by technology

However, the method of reducing the carrier lifetime to improve the reverse recovery characteristics and reduce the hole injection efficiency will increase the pressure drop of the forward conduction, and the method of injecting high-energy hydrogen ions, helium ions and other local recombination centers uses very expensive equipment. Not conducive to process production

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