Electro-luminescent porous silica material and its preparation method

Abstract

The invention relates to an electroluminescence porous silicon and relative preparation method, belonging to the electroluminescence porous silicon technique. Said invention is formed by a silicon base; a porous silicon layer above one side of silicon base; and a silicon line layer above porous silicon layer whose average diameter is 200-500 nanometers and length is 2-10 microns. The preparation method comprises: putting the washed silicon plate into the water solution of fluohydric acid and silver nitrate to be chemical etched; putting the etched silicon plate into the water solution of fluohydric acid and ethanol to be electrical chemical etched to attain the electroluminescence porous silicon. The invention has simple preparation process, and the electroluminescence porous silicon has a silicon line layer above the porous silicon layer with higher lighting ability than present electroluminescence porous silicon.

Description

Technical field:

[0001] The invention relates to electroluminescent porous silicon and a preparation method thereof, belonging to the technology of electroluminescent porous silicon materials. Background technique:

[0002] Porous silicon is a silicon-based nanoluminescent material. It has been widely studied by scientists at home and abroad due to its advantages of easy integration with existing silicon chips, low development cost, uniform light emission, and multi-color. It has become a silicon-based material since the 1990s. The main representative of nano-luminescent materials.

[0003] The porous silicon structure prepared by the traditional method is a common porous columnar loose structure. There are mainly the following methods for preparing the porous silicon with common structure and visible light emission performance: 1) Electrochemical anodic oxidation method. For example, in 1990, L.T.Canham first used silicon wafers as raw materials to prepare porous silicon ...

Examples

Embodiment 1

[0013] P-type, boron doped, resistivity 10-12Ωcm, crystal plane index (100), 2mm thick, 1×1cm 2 monocrystalline silicon wafers as raw materials. Clean with deionized water, acetone, and absolute ethanol in sequence, and stick one side with tape after drying. Prepare an etching solution of 3.0 mol / L hydrofluoric acid and 20 ml of 0.01 mol / L silver nitrate, heat to 50° C. under normal pressure, place the silicon wafer above, and keep it warm for 60 minutes. Then soak it in 10% dilute nitric acid for 4 days, take it out and dry it, remove the adhesive tape, place the etched side on the anode of the electrolytic cell, and the cathode is a graphite electrode. Select hydrofluoric acid 6ml, ethanol 9ml, deionized water 12ml (volume ratio) as the etching solution, with a current density of 80mA / cm 2 After etching for 20 minutes, electroluminescent porous silicon with silicon wire structure was obtained. The silicon wires have an average diameter of 235 nm and an average height of 8...

Embodiment 2

[0015] P-type, boron doped, resistivity 10-12Ωcm, crystal plane index (100), 2mm thick, 1×1cm 2 monocrystalline silicon wafers as raw materials. Clean with deionized water, acetone, and absolute ethanol in sequence, and stick one side with tape after drying. Prepare an etching solution of 3.0 mol / L hydrofluoric acid and 20 ml of 0.01 mol / L silver nitrate, heat to 60° C. under normal pressure, place the silicon wafer above, and keep it warm for 60 minutes. Then soak it in 10% dilute nitric acid for 4 days, take it out and dry it, remove the adhesive tape, place the etched side on the anode of the electrolytic cell, and the cathode is a graphite electrode. Select 1ml of hydrofluoric acid, 10ml of ethanol, and 10ml of deionized water (volume ratio) as the etching solution, and sequentially use a current density of 30mA / cm 2 Etching for 30 minutes and 20mA / cm 2 After etching for 30 minutes, electroluminescent porous silicon with a silicon line structure was obtained.

Embodiment 3

[0017] P-type, boron doped, resistivity 10-12Ωcm, crystal plane index (110), 2mm thick, 1×1cm 2 monocrystalline silicon wafers as raw materials. Clean with deionized water, acetone, and absolute ethanol in sequence, and stick one side with tape after drying. Prepare an etching solution of 1.5 mol / L hydrofluoric acid and 20 ml of 0.01 mol / L silver nitrate, heat to 40° C. under normal pressure, place the silicon wafer above, and keep it warm for 60 minutes. Then soak it in 10% dilute nitric acid for 4 days, take it out and dry it, remove the adhesive tape, place the etched side on the anode of the electrolytic cell, and the cathode is a graphite electrode. Select 6ml of hydrofluoric acid, 9ml of ethanol, and 12ml of deionized water (volume ratio) as the etching solution, and sequentially use a current density of 30mA / cm 2 Etching for 30 minutes and 20mA / cm 2 After etching for 30 minutes, electroluminescent porous silicon with a silicon line structure was obtained.

Technical field:

[0001] The invention relates to electroluminescent porous silicon and a preparation method thereof, belonging to the technology of electroluminescent porous silicon materials. Background technique:

[0002] Porous silicon is a silicon-based nanoluminescent material. It has been widely studied by scientists at home and abroad due to its advantages of easy integration with existing silicon chips, low development cost, uniform light emission, and multi-color. It has become a silicon-based material since the 1990s. The main representative of nano-luminescent materials.

[0003] The porous silicon structure prepared by the traditional method is a common porous columnar loose structure. There are mainly the following methods for preparing the porous silicon with common structure and visible light emission performance: 1) Electrochemical anodic oxidation method. For example, in 1990, L.T.Canham first used silicon wafers as raw materials to prepare porous silicon ...

Examples

Embodiment 1

[0013] P-type, boron doped, resistivity 10-12Ωcm, crystal plane index (100), 2mm thick, 1×1cm 2 monocrystalline silicon wafers as raw materials. Clean with deionized water, acetone, and absolute ethanol in sequence, and stick one side with tape after drying. Prepare an etching solution of 3.0 mol / L hydrofluoric acid and 20 ml of 0.01 mol / L silver nitrate, heat to 50° C. under normal pressure, place the silicon wafer above, and keep it warm for 60 minutes. Then soak it in 10% dilute nitric acid for 4 days, take it out and dry it, remove the adhesive tape, place the etched side on the anode of the electrolytic cell, and the cathode is a graphite electrode. Select hydrofluoric acid 6ml, ethanol 9ml, deionized water 12ml (volume ratio) as the etching solution, with a current density of 80mA / cm 2 After etching for 20 minutes, electroluminescent porous silicon with silicon wire structure was obtained. The silicon wires have an average diameter of 235 nm and an average height of 8...

Embodiment 2

[0015] P-type, boron doped, resistivity 10-12Ωcm, crystal plane index (100), 2mm thick, 1×1cm 2 monocrystalline silicon wafers as raw materials. Clean with deionized water, acetone, and absolute ethanol in sequence, and stick one side with tape after drying. Prepare an etching solution of 3.0 mol / L hydrofluoric acid and 20 ml of 0.01 mol / L silver nitrate, heat to 60° C. under normal pressure, place the silicon wafer above, and keep it warm for 60 minutes. Then soak it in 10% dilute nitric acid for 4 days, take it out and dry it, remove the adhesive tape, place the etched side on the anode of the electrolytic cell, and the cathode is a graphite electrode. Select 1ml of hydrofluoric acid, 10ml of ethanol, and 10ml of deionized water (volume ratio) as the etching solution, and sequentially use a current density of 30mA / cm 2 Etching for 30 minutes and 20mA / cm 2 After etching for 30 minutes, electroluminescent porous silicon with a silicon line structure was obtained.

Embodiment 3

[0017] P-type, boron doped, resistivity 10-12Ωcm, crystal plane index (110), 2mm thick, 1×1cm 2 monocrystalline silicon wafers as raw materials. Clean with deionized water, acetone, and absolute ethanol in sequence, and stick one side with tape after drying. Prepare an etching solution of 1.5 mol / L hydrofluoric acid and 20 ml of 0.01 mol / L silver nitrate, heat to 40° C. under normal pressure, place the silicon wafer above, and keep it warm for 60 minutes. Then soak it in 10% dilute nitric acid for 4 days, take it out and dry it, remove the adhesive tape, place the etched side on the anode of the electrolytic cell, and the cathode is a graphite electrode. Select 6ml of hydrofluoric acid, 9ml of ethanol, and 12ml of deionized water (volume ratio) as the etching solution, and sequentially use a current density of 30mA / cm 2 Etching for 30 minutes and 20mA / cm 2 After etching for 30 minutes, electroluminescent porous silicon with a silicon line structure was obtained.

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