Barrier adjustment method for silicon carbide Schottky diode

Abstract

The invention discloses a barrier adjustment method for a silicon carbide Schottky diode. According to the method, a layer of Al2O3 film is inserted into a Ti / 4H-SiC Schottky diode, and therefore, interface non-uniformity can be improved, and the height of a barrier can be adjusted. The Al2O3 thin film layer with different thicknesses is grown on an atomic layer through deposition before metal Tiis sputtered, subsequently, Al2O3 reacts with silicon carbide, so that a dipole layer can be formed, potential difference between two sides of an interface is caused, and therefore, the height of a Schottky barrier is reduced, and the power consumption of the device is reduced; the Al2O3 film and the silicon carbide can generate a positive barrier, and therefore the reverse leakage current of theSchottky diode can be reduced; the thicknesses of the Al2O3 thin film layer can be differently adjusted, so that different barrier heights are generated, and therefore, the adjustability of the heightof the barrier is realized.

Description

technical field [0001] The invention belongs to the technical field of microelectronic devices, and relates to a method for adjusting the potential barrier of a Schottky diode of the third-generation wide bandgap semiconductor material 4H-SiC. Background technique [0002] Compared with ordinary P-N junction diodes, Schottky diodes (SBDs) have the advantages of reduced forward voltage, short reverse recovery time and strong anti-surge current capability, etc., and are used in high-speed and high-efficiency rectifier circuits, microwave circuits and in high-speed integrated circuits. Schottky diodes use a metal as the positive electrode, the metal is selected from Au, Ag, Al, Pt, Mo, Ni, Ti, and an N-type semiconductor as the negative electrode, and the semiconductor is SiC. A metal-semiconductor device made of a barrier with rectifying properties. [0003] Today's semiconductor devices are constantly advancing in the direction of high energy and low price, and the process ...

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Problems solved by technology

[0004] Ti has low Schottky barrier height (SBH) as well as low forward voltage drop, but some unfavorable I-V characteristics tend to appear in Ti / SiC SBDs due to interface state, contamination caused by residual processing, inhomogeneity The impact of incomplete SBH, and the existing redemption to improve the interface unevenness and obtain a lower Schottky barrier height generally adopts heat treatment, but the heat treatment method cannot avoid silicidation and thermal budget, resulting in device power consumption and operating costs high

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