GaN Schottky diode and fabrication method thereof

Abstract

The invention relates to a GaN Schottky diode. The GaN Schottky diode comprises a substrate, an N+ GaN layer, an N-GaN layer table surface and a P-type GaN layer, wherein grooves are etched in the P-type GaN layer, Schottky metal layers are formed on the P-type GaN layer and are used as positive electrodes, and ohmic metal layers are formed on the N+ GaN layer and are used as negative electrodes. A fabrication method of the GaN Schottky diode comprises the steps of sequentially growing the N+ GaN layer, the N-GaN layer and the P-type GaN layer on an upper surface of the substrate; forming the table surface with the P-type GaN layer and the N-GaN layer, and partially etching the P-type GaN layer on each table surface to form a series of grooves; and depositing the Schottky metal layers on the P-type GaN layer to used as the positive electrodes, and depositing the ohmic metal layers on the N+GaN layer to be used as the negative electrodes. By the GaN Schottky diode, carriers under a Schottky electrode can be consumed, the Schottky barrier height is increased, the leakage current is reduced, the breakdown voltage is increased, the grooves under the Schottky electrode can be used for reducing the positive conduction voltage, so that the positive characteristic and the negative characteristic of the device are simultaneously improved.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a gallium nitride Schottky diode structure and a manufacturing method thereof. Background technique [0002] In the prior art, the structure of GaN Schottky diode is as follows figure 1 Shown: N+GaN layer 2 and N-GaN layer 3 are grown on sapphire, silicon or SiC substrate 1, N-GaN layer 3 is etched to N+GaN layer 2, and N-GaN layer A Schottky metal layer 5 is deposited on the GaN layer 3 as an anode, and an ohmic metal layer 6 is deposited on the N+GaN layer 2 as a cathode, thereby forming a Schottky diode. [0003] The disadvantage of the existing Gallium Nitride Schottky diode structure is that since the intrinsic Gallium Nitride is N-type, the electron concentration in the N-type GaN layer is limited by doping during the growth process, so it cannot be effectively Increase the Schottky barrier height to achieve the purpose of reducing leakage current and increasing breakdown vo...

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Problems solved by technology

[0003] The disadvantage of the existing Gallium Nitride Schottky diode structure is that since the intrinsic Gallium Nitride is N-type, the electron concentration in the N-type GaN layer is limited by doping during the growth process, so it cannot be effectively Increase the Schottky barrier height to reduce the leakage current and increase the breakdown voltage

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