Manufacturing method of Schottky diode with high reverse-blocking performance

Abstract

The invention provides a schottky diode with high reverse-blocking performance and a manufacturing method thereof. The schottky diode core is structurally characterized in that: a lightly doped epitaxial layer of a drift region is provided with a P-type structure region which is composed of a P-type ring and P-type dot matrixes uniformly spaced on the epitaxial layer in the P-type ring; the surface of the epitaxial layer in the P-type ring is provided with a schottky potential barrier contact metal layer; and the surface of the P-type structure region is in Ohm metal contact. When the schottky diode is in reverse application, a PN junction depletion region gradually spreads to a channel region along with the increase of the reverse voltage until the depletion region is communicated, and extends towards the substrate along with further increase of the reverse voltage to form an effective potential barrier in the channel region and effectively shield the schottky potential barrier region, thereby improving the reverse blocking ability that the reverse blocking voltage can reach 200 V or above; and moreover, the schottky diode also has good technical indexes such as reverse recovery time, reverse leakage current and the like, realizes low working loss of switches and prevents noise.

Description

technical field [0001] The invention relates to a Schottky diode and a manufacturing method thereof, in particular to a Schottky diode with improved reverse blocking characteristics and a manufacturing method thereof. Background technique [0002] Schottky diode is a high-current, ultra-high-speed, low-power rectification semiconductor device. It is an ideal device for high-frequency, low-voltage, high-current rectification, freewheeling and switch protection. Power electronic devices are gradually developing into high-frequency technology. It also promotes the technical development of Schottky diode technology in reducing power consumption and improving efficiency. It is a semiconductor device made of the metal-semiconductor junction principle that uses the surface barrier of the metal-semiconductor contact surface to produce rectification characteristics. The difference from the PN junction semiconductor device is that the Schottky diode is relatively conductive with minor...

AI Technical Summary

Problems solved by technology

The semiconductor region of the Schottky diode needs to adopt a lightly doped and thick drift region structure to withstand reverse blocking. To obtain high blocking capability, the current processing technology can only increase the thickness and resistivity of the drift region, but this will make the drift region The equivalent series resistance increases rapidly with the increase of the reverse breakdown voltage in a square relationship, and the forward voltage drop also increases significantly, and the reverse blocking characteristics become soft, resulting in a large reverse leakage current, so it will be strictly limited Application of Schottky Diodes in High Blocking Voltage Environment

Since the increase of the reverse blocking voltage is also affected by the lowering of the Schottky barrier, the reverse blocking characteristics are deteriorated, the blocking voltage is low, and the reverse leakage current is not saturated, so the reverse of the general Schottky diode The blocking voltage can only be within 100V, and it cannot be applied to high-voltage circuits with a reverse blocking voltage of 200V.

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