CN-115663016-B - Schottky diode, preparation method and chip

Abstract

The application belongs to the technical field of semiconductors, and provides a Schottky diode, a preparation method and a chip, wherein the Schottky diode comprises a semiconductor substrate, a channel layer, a first barrier layer, a second barrier layer, a first P column, a second P column, a cathode electrode unit and an anode electrode unit; according to the application, the anode electrode unit is made of Schottky metal, and is contacted with the first P column and the second P column, so that Schottky contact is formed between the anode electrode unit and the first P column, schottky contact is formed between the anode electrode unit and the second P column, and a higher Schottky barrier height exists between the anode electrode unit and the first P column and between the anode electrode unit and the second P column, so that leakage current of the anode electrode unit is reduced, higher forward threshold voltage is provided, and breakdown voltage of the Schottky diode is improved.

Inventors

• WANG WEI
• HUANG HUIQIN

Assignees

• 天狼芯半导体(成都)有限公司

Dates

Publication Date

20260505

Application Date

20221025

Claims (10)

1. 1. A Schottky diode is characterized in that, the schottky diode includes: a semiconductor substrate; A channel layer disposed on the semiconductor substrate; A first barrier layer provided on the semiconductor substrate and in contact with a first surface of the channel layer; A second barrier layer provided on the semiconductor substrate and in contact with the second surface of the channel layer; a first P column arranged on the semiconductor substrate, wherein the first barrier layer is arranged between the first P column and the channel layer; A second P column arranged on the semiconductor substrate, and the second barrier layer is arranged between the second P column and the channel layer; A cathode electrode unit disposed on the semiconductor substrate, and in contact with the first end of the channel layer, the first end of the first barrier layer, and the first end of the second barrier layer, respectively; The anode electrode unit is L-shaped, wherein a vertical part of the anode electrode unit is arranged on the semiconductor substrate, the vertical part is respectively contacted with a second end of the channel layer, a second end of the first barrier layer and a second end of the second barrier layer, a horizontal part of the anode electrode unit is arranged on the first P column, the second P column, the channel layer, the first barrier layer and the second barrier layer, the anode electrode unit is Schottky metal, schottky contact is formed between the anode electrode unit and the first P column, and Schottky contact is formed between the anode electrode unit and the second P column.
2. 2. The schottky diode of claim 1 wherein said anode electrode unit comprises: a first anode subunit disposed on the semiconductor substrate and respectively contacted with the second end of the channel layer, the second end of the first barrier layer and the second end of the second barrier layer; And the metal field plate subunit is arranged on the first P column, the second P column, the channel layer, the first barrier layer and the second barrier layer.
3. 3. The schottky diode of claim 1 wherein said anode electrode element is a schottky metal and said cathode electrode element is an ohmic metal.
4. 4. The schottky diode of claim 2 wherein the height of said cathode electrode unit is equal to the sum of the heights of said first anode sub-unit and said metal field plate sub-unit.
5. 5. The schottky diode of claim 1 wherein said first P-pillar and said second P-pillar are disposed opposite each other.
6. 6. The schottky diode of claim 2 wherein the distance of said first P-pillar to said cathode electrode unit is the same as the distance of said first P-pillar to said first anode subunit.
7. 7. The schottky diode of any of claims 1-6 wherein the length of the first P-pillar is less than the length of the first barrier layer.
8. 8. The schottky diode of claim 6 wherein the length of said first P-pillar is 1/3 the length of said first barrier layer.
9. 9. A chip, comprising a plurality of schottky diodes according to any one of claims 1 to 8, wherein a plurality of the schottky diodes are commonly disposed on the same semiconductor substrate, cathode electrode units of the plurality of the schottky diodes are commonly connected, and anode electrode units of the plurality of the schottky diodes are commonly connected.
10. 10. A method of manufacturing a schottky diode as described in any of claims 1-8, comprising: sequentially forming a first P column, a channel layer and a second P column at intervals on a semiconductor substrate; Forming a first barrier layer on the semiconductor substrate, wherein the first barrier layer is positioned between the first P column and the channel layer; forming a second barrier layer on the semiconductor substrate, wherein the second barrier layer is positioned between the second P column and the channel layer; forming a cathode electrode unit on the semiconductor substrate, wherein the cathode electrode unit is respectively contacted with a first end of the channel layer, a first end of the first barrier layer and a first end of the second barrier layer; the anode electrode unit is L-shaped, the vertical part of the anode electrode unit is arranged on the semiconductor substrate and is respectively contacted with the second end of the channel layer, the second end of the first barrier layer and the second end of the second barrier layer, and the horizontal part of the anode electrode unit is arranged on the first P column, the second P column, the channel layer, the first barrier layer and the second barrier layer.

Description

Schottky diode, preparation method and chip Technical Field The application belongs to the technical field of semiconductors, and particularly relates to a Schottky diode, a preparation method and a chip. Background As a high-tech industry, the electronic information industry plays an important role in expanding social employment, promoting economic transformation and upgrading, enhancing international competitiveness, maintaining national security and the like. The power diode is a key component of a circuit system, and is widely applied to civil products such as high-frequency inverters, digital products, generators, televisions and the like, satellite receiving devices, various advanced weapon control systems such as missiles, aircrafts and the like, and military occasions of instruments and meter equipment. The common rectifier diode, the schottky diode, the PN diode and the like are commonly used, wherein the schottky rectifier tube has the advantages of low on-state voltage drop, large leakage current, almost zero reverse recovery time and the like, and is very widely used. Schottky diodes are diodes fabricated using the metal-semiconductor junction principle formed by metal-semiconductor contacts. Schottky diodes have the advantages of lower power consumption, higher current and ultra-high speed than PN junction diodes, and are therefore favored in electronics. However, the existing schottky diode has the problem of low breakdown voltage. Disclosure of Invention In order to solve the technical problems, the embodiment of the application provides a schottky diode, a preparation method and a chip, and aims to solve the problem that the existing schottky diode has lower breakdown voltage. A first aspect of an embodiment of the present application provides a schottky diode, including: a semiconductor substrate; A channel layer disposed on the semiconductor substrate; A first barrier layer provided on the semiconductor substrate and in contact with a first surface of the channel layer; A second barrier layer provided on the semiconductor substrate and in contact with the second surface of the channel layer; a first P column arranged on the semiconductor substrate, wherein the first barrier layer is arranged between the first P column and the channel layer; A second P column arranged on the semiconductor substrate, and the second barrier layer is arranged between the second P column and the channel layer; A cathode electrode unit disposed on the semiconductor substrate, and in contact with the first end of the channel layer, the first end of the first barrier layer, and the first end of the second barrier layer, respectively; The anode electrode unit is L-shaped, wherein the vertical part of the anode electrode unit is arranged on the semiconductor substrate and is respectively contacted with the second end of the channel layer, the second end of the first barrier layer and the second end of the second barrier layer, and the horizontal part of the anode electrode unit is arranged on the first P column, the second P column, the channel layer, the first barrier layer and the second barrier layer. In one embodiment, the anode electrode unit includes: a first anode subunit disposed on the semiconductor substrate and respectively contacted with the second end of the channel layer, the second end of the first barrier layer and the second end of the second barrier layer; And the metal field plate subunit is arranged on the first P column, the second P column, the channel layer, the first barrier layer and the second barrier layer. In one embodiment, the anode electrode unit is a schottky metal and the cathode electrode unit is an ohmic metal. In one embodiment, the height of the cathode electrode unit is equal to the sum of the heights of the first anode sub-unit and the metal field plate sub-unit. In one embodiment, the first P-pillar and the second P-pillar are disposed opposite each other. In one embodiment, the distance from the first P-pillar to the cathode electrode unit is the same as the distance from the first P-pillar to the first anode subunit. In one embodiment, the length of the first P-pillar is less than the length of the first barrier layer. In one embodiment, the length of the first P-pillar is 1/3 of the length of the first barrier layer. A second aspect of the present application provides a chip, including a plurality of schottky diodes as described in any one of the foregoing, where a plurality of the schottky diodes are disposed on a same semiconductor substrate, cathode electrode units of the plurality of the schottky diodes are connected together, and anode electrode units of the plurality of the schottky diodes are connected together. A third aspect of the present application provides a method for manufacturing a schottky diode, including: sequentially forming a first P column, a channel layer and a second P column at intervals on a semiconductor substrate; Forming a first barrier layer on