Low-power-consumption high-reliability half-packaged trench gate MOSFET device and preparation method thereof

Abstract

The invention provides a low-power-consumption high-reliability semi-wrapped trench gate silicon carbide MOSFET device and a preparation method thereof. The low-power-consumption high-reliability semi-wrapped trench gate silicon carbide MOSFET device comprises an N-type substrate, an N-type epitaxial layer, a first P-body region, a first P + contact region, a first N + contact region, a second P-body region, a second P + contact region, a second N + contact region, a gate medium, a trench gate, an auxiliary trench gate, a source electrode and a drain electrode. Compared with a traditional half-wrapped trench gate silicon carbide MOSFET, the gate dielectric is protected by forming the second P-body region at the bottom of the trench, the reliability of the gate dielectric of the device is enhanced, a part of gate-drain capacitance is shielded, the switching loss of the device is reduced on the basis of not sacrificing the conduction capability of the original trench MOSFET, and when the device is short-circuited, the drain voltage is relatively large, so that the reliability of the device is improved. And at the moment, the JFET region between the second P-body region and the first P + contact region is pinched off, so that the saturation current of the device is reduced, and the short-circuit capability of the device is improved.

Description

technical field [0001] The invention belongs to the technical field of power semiconductor devices, in particular to a low power consumption and high reliability half-pack trench gate silicon carbide MOSFET device and a preparation method thereof. Background technique [0002] As one of the representatives of the third generation of wide-bandgap semiconductor materials, silicon carbide (Silicon Carbide) material has a wider band gap (3 times) than silicon material, a higher critical electric field (10 times), a higher load The advantages of the current saturation drift speed (2 times), higher thermal conductivity (2.5 times), etc., are excellent materials for the preparation of high-voltage power electronic devices. application prospects. [0003] MOSFET is one of the most widely used gate-controlled devices in silicon carbide power devices. Since SiC MOSFET is a device characterized by a unipolar transport mechanism, only one of the electrons or holes conducts electricity...

AI Technical Summary

Problems solved by technology

Although the traditional half-encapsulated trench gate MOSFET can provide strong protection for the gate dielectric and improve the reliability of the gate dielectric of the device, it sacrifices half of the channel density, which increases the on-resistance of the device and increases the conduction loss.

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