Resistance region integrated VDMOS device

Abstract

The invention relates to a resistance region integrated VDMOS device. A first conduction type Ohm contact region and a first conduction type body region are arranged between cell grooves; charges areinjected into a gate dielectric layer; in a forward conduction state of VDMOS, the gate dielectric layer and the first conduction type body region form an accumulation layer; a second conduction typebody region does not exist between the cell grooves, and the conduction resistance is remarkably reduced. in a body diode conduction state, after a small quantity of minority carrier charges are injected, the first conduction type Ohm contact region and the first conduction type body region can be conducted so as to reduce forward conduction pressure drop of the body diode; meanwhile, the conduction mechanism is dominated by a monopole type, the concentration of the minority carriers in a first conduction type drift region is relatively low, and the reverse recovery feature of the body diode is remarkably enhanced. in a blocking state of VDMOS, the charges in the gate dielectric layer can form a depletion region; compared with existing VDMOS structure, the voltage resistance is kept unchanged.

Description

technical field [0001] The invention relates to a VDMOS device, in particular to a VDMOS device with an integrated resistance area, and belongs to the technical field of VDMOS devices. Background technique [0002] VDMOS is the most widely used type of power device in power semiconductors. It has the advantages of high input impedance, easy driving, fast switching speed, and good thermal stability. In the low-voltage field, the trench-gate VDMOS device is widely used because it eliminates the resistance of the JFET region and has a smaller cell size, so it has a lower specific on-resistance. [0003] Superjunction MOSFET is an important power device that has appeared in recent years. Its basic principle is the principle of charge balance. By introducing superjunction structure into the drift region of ordinary power MOSFET, the on-resistance and breakdown of ordinary MOSFET are greatly improved. The compromise relationship between voltages has been widely used in power syst...

AI Technical Summary

Problems solved by technology

However, electron irradiation will increase the on-resistance of VDMOS, and at the same time, its electronic irradiation thermal stability is poor, and its characteristics are easy to degrade

The integrated Schottky diode, under high temperature conditions, has a large leakage current

[0006] In order to further solve the problem of large reverse bias leakage current of the Schottky diode, an integrated MOS diode is proposed, and the MOS gate is used to control the diode to be turned on or off. Resistors and MOS diodes have complex cell structures and large sizes. At the same time, the threshold voltage of MOS diodes needs to be adjusted, and the process and structure are complicated.

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