# US 7,612,426 B2 · Schottky barrier diode and diode array

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 7,612,426 B2
- Document ID: US7612426B2
- Status: Granted
- Kind: B2
- Application number: 11/272,878
- Filed: 2005-11-15
- Published: 2006-05-25
- Granted: 2009-11-03
- Earliest claimed: 2004-11-25
- Assignees: Panasonic Corporation
- Inventors: Manabu Yanagihara; Yasuhiro Uemoto; Tsuyoshi Tanaka; Daisuke Ueda
- Web page: https://patentgrep.com/patent/US7612426B2

## CPC

- H10D 8/60: Schottky-barrier diodes
- H10D 8/051: {of Schottky diodes}
- H10D 62/126: {Top-view geometrical layouts of the regions or the junctions}
- H10D 64/23: Electrodes carrying the current to be rectified, amplified, oscillated or switched, e.g. sources, drains, anodes or cathodes
- H10D 84/01: Manufacture or treatment
- H10D 84/221: {of only diodes}
- H10W 20/0245: {comprising use of blind vias during the manufacture}
- H10P 30/204: {into Group IV semiconductors}
- H10P 30/208: {of electrically inactive species}
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10

## Abstract

A Schottky barrier diode includes a first semiconductor layer and a second semiconductor layer successively formed above a semiconductor substrate with a buffer layer formed between the first and second semiconductor layers and the semiconductor substrate. A Schottky electrode and an ohmic electrode spaced from each other are formed on the second semiconductor layer, and a back face electrode is formed on the back face of the semiconductor substrate. The Schottky electrode or the ohmic electrode is electrically connected to the back face electrode through a via penetrating through at least the buffer layer.

## Claims

### Claim 1

A Schottky barrier diode comprising:
a first semiconductor layer and a second semiconductor layer successively formed above a semiconductor substrate with a buffer layer disposed between said first and second semiconductor layers and said semiconductor substrate;
a Schottky electrode and an ohmic electrode spaced from each other and formed on said second semiconductor layer; and
a back face electrode formed on a back face of said semiconductor substrate,
wherein said ohmic electrode is electrically connected to said back face electrode through a via penetrating through at least said buffer layer, and
said Schottky electrode surrounds said ohmic electrode.

### Claim 2 (depends on 1)

The Schottky barrier diode of claim 1, wherein said via does not penetrate through said semiconductor substrate.

### Claim 3 (depends on 1)

The Schottky barrier diode of claim 1, wherein said ohmic electrode is in a circular shape in a plan view and a side of said Schottky electrode opposing said ohmic electrode is in a circular shape.

### Claim 4 (depends on 1)

The Schottky barrier diode of claim 1, wherein said ohmic electrode is in a rectangular shape in a plan view and sides of said Schottky electrode opposing said ohmic electrode are in a rectangular shape.

### Claim 5 (depends on 1)

The Schottky barrier diode of claim 1, wherein said ohmic electrode is in a hexagonal shape in a plan view and sides of said Schottky electrode opposing said ohmic electrode are in a hexagonal shape.

### Claim 6 (depends on 1)

The Schottky barrier diode of claim 1, wherein a plane shape of an outer circumference of said Schottky electrode is similar to a plane shape of an inner circumference of said Schottky electrode.

### Claim 7 (depends on 1)

The Schottky barrier diode of claim 1, wherein said Schottky electrode has at least one cut portion.

### Claim 8 (depends on 1)

The Schottky barrier diode of claim 1, wherein
a high-resistance region surrounding said Schottky electrode and having higher resistance than said first semiconductor layer and said second semiconductor layer is formed on a side of said Schottky electrode not opposing said ohmic electrode, and
said high-resistance region is formed by thermally oxidizing given portions of said first semiconductor layer and said second semiconductor layer.

### Claim 9 (depends on 1)

The Schottky barrier diode of claim 1, wherein said semiconductor substrate is made of silicon, silicon carbide or gallium nitride.

### Claim 10 (depends on 1)

The Schottky barrier diode of claim 1, wherein each of said first semiconductor layer and said second semiconductor layer is made of a compound represented by a general formula, InaGabAlcBdN, wherein 0≦a, b, c, d≦1 and a+b+c+d=1, and said second semiconductor layer has a larger band gap than said first semiconductor layer.

### Claim 11 (depends on 1)

The Schottky barrier diode of claim 1, wherein
a high-resistance region surrounding said Schottky electrode and having higher resistance than said first semiconductor layer and said second semiconductor layer is formed on a side of said Schottky electrode not opposing said ohmic electrode, and
said high-resistance region is formed by ion implantation.

### Claim 12 (depends on 1)

The Schottky barrier diode of claim 1, wherein said drawing electrode and said Schottky electrode are electrically connected to each other through another via penetrating through said first insulating film.

### Claim 13 (depends on 1)

The Schottky barrier diode of claim 1, further comprising:
a first insulating film formed on said Schottky electrode and said ohmic electrode; and
a drawing electrode drawn onto said first insulating film,
wherein said Schottky electrode is electrically connected to said drawing electrode only through a metal.

### Claim 14 (depends on 13)

The Schottky barrier diode of claim 13, wherein said drawing electrode covers said first insulating film above said ohmic electrode.

### Claim 15

A diode array comprising a plurality of Schottky barrier diodes formed on one semiconductor substrate and connected to one another in parallel,
wherein said plurality of Schottky barrier diodes include:
a first semiconductor layer and a second semiconductor layer successively formed above said semiconductor substrate with a buffer layer disposed between said first and second semiconductor layers and said semiconductor substrate;
a plurality of electrode pairs each corresponding to a pair of a Schottky electrode and an ohmic electrode formed on said second semiconductor layer and spaced from each other;
a first insulating film formed on said second semiconductor layer for covering said plurality of electrode pairs;
a drawing electrode formed on said first insulating film; and
a back face electrode formed on a back face of said semiconductor substrate,
said ohmic electrode of each of said plurality of electrode pairs is electrically connected to said back face electrode through a via penetrating through at least said buffer layer,
said Schottky electrode of each of said plurality of electrode pairs is electrically connected to said drawing electrode, and
wherein said Schottky electrode surrounds said ohmic electrode in each of said plurality of electrode pairs.

### Claim 16 (depends on 15)

The diode array of claim 15, wherein said ohmic electrode is in a circular shape in a plan view and a side of said Schottky electrode opposing said ohmic electrode is in a circular shape in each of said plurality of electrode pairs.

### Claim 17 (depends on 15)

The diode array of claim 15, wherein said ohmic electrode is in a rectangular shape in a plan view and sides of said Schottky electrode opposing said ohmic electrode are in a rectangular shape in each of said plurality of electrode pairs.

### Claim 18 (depends on 15)

The diode array of claim 15, wherein said ohmic electrode is in a hexagonal shape in a plan view and sides of said Schottky electrode opposing said ohmic electrode are in a hexagonal shape in each of said plurality of electrode pairs.

### Claim 19 (depends on 15)

The diode array of claim 15, wherein a plane shape of an outer circumference of said Schottky electrode is similar to a plane shape of an inner circumference of said Schottky electrode in each of said plurality of electrode pairs.

### Claim 20 (depends on 15)

The diode array of claim 15, wherein each Schottky electrode has at least one cut portion.

### Claim 21 (depends on 15)

The diode array of claim 15, wherein adjacent ones of said plurality of Schottky barrier diodes are in contact with each other.

### Claim 22 (depends on 15)

The diode array of claim 15, wherein
a region where said plurality of Schottky barrier diodes are disposed is surrounded with a high-resistance region having higher resistance than said first semiconductor layer and said second semiconductor layer, and
said high-resistance region is formed by thermally oxidizing given portions of said first semiconductor layer and said second semiconductor layer.

### Claim 23 (depends on 15)

The diode array of claim 15, wherein said semiconductor substrate is made of silicon, silicon carbide or gallium nitride.

### Claim 24 (depends on 15)

The diode array of claim 15, wherein each of said first semiconductor layer and said second semiconductor layer is made of a compound represented by a general formula, InaGabAlcBdN, wherein 0≦a, b, c, d≦1 and a+b+c+d=1, and said second semiconductor layer has a larger band gap than said first semiconductor layer.

### Claim 25 (depends on 15)

The diode array of claim 15,
wherein a high-resistance region surrounding said Schottky electrode and having higher resistance than said first semiconductor layer and said second semiconductor layer is formed on a side of said Schottky electrode not opposing said ohmic electrode, and
said high-resistance region is formed by ion implantation.

### Claim 26 (depends on 15)

The diode array of claim 15, wherein said via does not penetrate through said semiconductor substrate.

### Claim 27 (depends on 15)

The diode array of claim 15, wherein said drawing electrode covers said first insulating film above said ohmic electrode of each of said plurality of electrode pairs.

### Claim 28 (depends on 15)

The diode array of claim 15, wherein said Schottky electrode of each of said plurality of electrode pairs is electrically connected to said drawing electrode only through a metal.