Schottky diode and method of formation of Schottky diode

Abstract

The invention discloses a Schottky diode and a method of formation of the Schottky diode. The method of formation of the Schottky diode comprises the following steps: providing a semiconductor substrate and forming a plurality of grooves inside the semiconductor substrate; obliquely injecting P type ions into the semiconductor substrate, and forming first P type doped regions inside the semiconductor substrate close to a surface of the semiconductor substrate, sidewalls of the grooves and a bottom surface; fully filling the grooves with polycrystalline silicon material; inversely forming N type doped regions inside the semiconductor substrate close to the surface and the polycrystalline silicon material; and forming Schottky metal layers on the surface of the semiconductor substrate and the surface of the polycrystalline silicon material. For the spacing between two first P type doped regions of adjacent grooves is less than the spacing between the adjacent grooves, the semiconductor substrate between the two first P type doped regions of the adjacent grooves in the Schottky diode can be cut off by a depletion region more easily when an inverse voltage is applied to two ends of the Schottky diode, so that the inverse breakdown voltage of the Schottky diode can be increased.

Description

technical field [0001] The invention relates to the field of semiconductor manufacturing, in particular to a Schottky diode and a forming method thereof. Background technique [0002] Schottky Barrier Diode (Schottky Barrier Diode) is a low-power, high-current, ultra-high-speed semiconductor device. The metal layer is used as the positive electrode and the semiconductor substrate is used as the negative electrode. The potential barrier formed on the contact surface of the two has rectification characteristics. made. Its reverse recovery time is short (can be as small as a few nanoseconds), the forward voltage is low (0.4 volts), and the rectification current is large (up to several thousand amperes), so it is widely used in switching power supplies, frequency converters, drives, etc. [0003] The U.S. patent document with the publication number US2004 / 0007723A1 discloses a trench Schottky diode. For the specific structure, please refer to figure 1 , including: an N-type do...

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Problems solved by technology

However, when the distance between the two trenches is small, the conduction area becomes narrower, the forward conduction resistance becomes larger, and the conduction loss becomes larger.

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