Schottky barrier diode and preparation method thereof

Abstract

The invention provides a schottky barrier diode and a preparation method thereof. The schottky barrier diode has a structure that an N-type semiconductor is used as a substrate, an N-epitaxial layer is formed on the substrate and a positive electrode is a (blocking layer) metallic material. The preparation method comprises the following steps: cleaning for 10 to 30 minutes with a cleaning reagent of 75 degrees between a silicon epitaxial wafer and a metal to grow a layer of thin oxide layer, wherein the thickness of the oxide layer is between 20 and 100 angstroms; and sputtering or evaporating the metal to ensure that an alloy forms a silicide which servers as a barrier layer so as to form the schottky barrier diode. The preparation method is simple and reduces the barrier height through the participation of the thin oxide layer under the condition with a low cost, the efficient preparation obtains a low forward voltage drop schottky barrier diode, and compared with the conventional diode structure, the schottky barrier diode has a more extensive application range.

Description

technical field

[0001] The invention belongs to the technical field of diodes and their preparation, in particular to a Schottky barrier diode and its preparation method. Background technique

[0002] Schottky Barrier Diode (SBD) is widely used in DC-DC Converter, Voltage Regulator Module VRM, Telecom / Server, AC Power adapter (Adaptor) and charger (Charger), etc. Instructions attached figure 1 It is a schematic diagram of the structure of a Schottky barrier diode, as shown in the figure, the preparation method of the Schottky barrier diode is to deposit a barrier metal on a silicon epitaxial wafer, or form a metal silicide to form a barrier layer, on which The growth contact metal is used as the lead wire, and the high voltage product generally has a diffusion guard ring.

[0003] The invention patent (patent number 02127232.8) applied by Sanyo Electric Co., Ltd. of Japan discloses a manufacturing method of Schottky barrier diodes. InGaP layers are laminated on the surfac...

Examples

Embodiment 1

[0032] A thin oxide layer is grown between the silicon epitaxial wafer and the metal, the thickness of the oxide layer is Then sputter or evaporate the metal, and clean the thin oxide layer with a mixed solution of ammonia, hydrogen peroxide and water at a ratio of 1:2:8 at 75°C for 30 minutes, and the alloy forms a silicide as a barrier layer.

[0033] The obtained diode barrier height is 0.629, and the oxide layer thickness is The forward voltage drop is 0.541V.

Embodiment 2

[0035] A thin oxide layer is grown between the silicon epitaxial wafer and the metal, the thickness of the oxide layer is Then sputter or evaporate the metal, and clean the thin oxide layer with a mixed solution of ammonia, hydrogen peroxide and water at a ratio of 1:2:8 at 75°C for 20 minutes, and the alloy forms a silicide as a barrier layer.

[0036] The obtained diode barrier height is 0.624v, and the oxide layer thickness is The forward voltage drop is 0.543V.

Embodiment 3

[0038] A thin oxide layer is grown between the silicon epitaxial wafer and the metal, the thickness of the oxide layer is Then sputter or evaporate the metal, and clean the thin oxide layer with a mixed solution of ammonia, hydrogen peroxide and water at a ratio of 1:2:8 at 75°C for 10 minutes, and the alloy forms a silicide as a barrier layer.

[0039] The barrier height of the obtained diode is 0.655v, and the thickness of the oxide layer is The forward voltage drop is 0.580V. The oxide layer grown in this way is easy to operate, low in cost, and can remove surface particles to improve the yield.

technical field

[0001] The invention belongs to the technical field of diodes and their preparation, in particular to a Schottky barrier diode and its preparation method. Background technique

[0002] Schottky Barrier Diode (SBD) is widely used in DC-DC Converter, Voltage Regulator Module VRM, Telecom / Server, AC Power adapter (Adaptor) and charger (Charger), etc. Instructions attached figure 1 It is a schematic diagram of the structure of a Schottky barrier diode, as shown in the figure, the preparation method of the Schottky barrier diode is to deposit a barrier metal on a silicon epitaxial wafer, or form a metal silicide to form a barrier layer, on which The growth contact metal is used as the lead wire, and the high voltage product generally has a diffusion guard ring.

[0003] The invention patent (patent number 02127232.8) applied by Sanyo Electric Co., Ltd. of Japan discloses a manufacturing method of Schottky barrier diodes. InGaP layers are laminated on the surfac...

Examples

Embodiment 1

[0032] A thin oxide layer is grown between the silicon epitaxial wafer and the metal, the thickness of the oxide layer is Then sputter or evaporate the metal, and clean the thin oxide layer with a mixed solution of ammonia, hydrogen peroxide and water at a ratio of 1:2:8 at 75°C for 30 minutes, and the alloy forms a silicide as a barrier layer.

[0033] The obtained diode barrier height is 0.629, and the oxide layer thickness is The forward voltage drop is 0.541V.

Embodiment 2

[0035] A thin oxide layer is grown between the silicon epitaxial wafer and the metal, the thickness of the oxide layer is Then sputter or evaporate the metal, and clean the thin oxide layer with a mixed solution of ammonia, hydrogen peroxide and water at a ratio of 1:2:8 at 75°C for 20 minutes, and the alloy forms a silicide as a barrier layer.

[0036] The obtained diode barrier height is 0.624v, and the oxide layer thickness is The forward voltage drop is 0.543V.

Embodiment 3

[0038] A thin oxide layer is grown between the silicon epitaxial wafer and the metal, the thickness of the oxide layer is Then sputter or evaporate the metal, and clean the thin oxide layer with a mixed solution of ammonia, hydrogen peroxide and water at a ratio of 1:2:8 at 75°C for 10 minutes, and the alloy forms a silicide as a barrier layer.

[0039] The barrier height of the obtained diode is 0.655v, and the thickness of the oxide layer is The forward voltage drop is 0.580V. The oxide layer grown in this way is easy to operate, low in cost, and can remove surface particles to improve the yield.

Images