Semiconductor silicon wafer corrosive liquid and corrosion method thereof

Abstract

The invention relates to the technical field of microelectronic processing and especially to a semiconductor silicon wafer corrosive liquid. The semiconductor silicon wafer corrosive liquid is formed by mixing nitric acid, hydrofluoric acid, and glacial acetic acid according to a volume ratio of 4-14: 4-14: 6-18. A semiconductor silicon wafer is placed in a closed container containing the semiconductor silicon wafer corrosive liquid in order to be corroded on a low-temperature condition. Different corrosion demands are satisfied by regulating the ratio of the nitric acid to the hydrofluoric acid. The corrosion rate and the corrosion depth of the semiconductor silicon wafer, and the surface cleanliness of the corroded semiconductor silicon wafer can be controlled on the low-temperature condition. The corrosion rate at a low-temperature environment is less than that at a normal-temperature environment, so the corrosive uniformity of the semiconductor silicon wafer is easier to control. The semiconductor silicon wafer corrosive liquid is easy to form, attainable in raw material, low in cost, and very suitable for industrial production of semiconductor microelectronics.

Description

technical field

[0001] The invention relates to the technical field of microelectronic processing, in particular to a semiconductor silicon wafer etching solution and an etching method thereof. Background technique

[0002] In the microelectronics processing technology, the semiconductor wafer manufacturing process generally includes the following steps: providing a wafer inverted garden obtained by cutting and slicing a single crystal block, mechanical polishing, etching, polishing and cleaning, and producing a wafer with high-precision flatness wafer. Wafers that have undergone mechanical treatments such as dicing, OD grinding, slicing, grinding, etc. have a damaged layer, that is, a process-damaged layer on one of its surfaces that causes slippage, dislocation, etc. during device fabrication Crystal defects reduce the mechanical strength of the wafer and adversely affect the electrical properties. Therefore, this layer must be completely removed. In order to remove the p...

Examples

Embodiment 1

[0017] A semiconductor silicon wafer etching solution is prepared by mixing 65% nitric acid, 45% hydrofluoric acid and 95% glacial acetic acid according to the volume ratio of 4:4:6.

[0018] The etching method for the semiconductor silicon wafer by the etching solution comprises placing the semiconductor silicon wafer in a closed container filled with the etching solution, and performing etching under low temperature conditions, and the low temperature is -12°C.

[0019] Inert gas nitrogen was passed into the container. The flow rate is 1 sccm.

[0020] After the semiconductor silicon wafer is etched, the silicon wafer needs to be cleaned.

[0021] For cleaning, use high-purity deionized water with a resistivity greater than 18MΩ*cm to perform flow cleaning on the etched silicon wafer until the surface of the silicon wafer is clean.

Embodiment 2

[0023] A semiconductor silicon wafer etching solution is prepared by mixing 70% nitric acid, 55% hydrofluoric acid and 99% glacial acetic acid according to the volume ratio of 14:14:18.

[0024] The method for etching semiconductor silicon wafers by the etching solution comprises placing the semiconductor silicon wafers in an airtight container filled with etching solutions, and performing etching under low temperature conditions, the low temperature being -8°C.

[0025] The container is filled with inert gas argon. The flow rate is 800 sccm.

[0026] After the semiconductor silicon wafer is etched, the silicon wafer needs to be cleaned.

[0027] For cleaning, use high-purity deionized water with a resistivity greater than 18MΩ*cm to perform flow cleaning on the etched silicon wafer until the surface of the silicon wafer is clean.

Embodiment 3

[0029] A semiconductor silicon wafer etching solution is prepared by mixing 66% nitric acid, 48% hydrofluoric acid and 97% glacial acetic acid according to the volume ratio of 6:6:8.

[0030] The etching method for the semiconductor silicon wafer by the etching solution comprises placing the semiconductor silicon wafer in an airtight container filled with the etching solution, and performing etching under low temperature conditions, the low temperature being -10°C.

[0031] The container is filled with inert gas helium. The flow rate is 500 sccm.

[0032] After the semiconductor silicon wafer is etched, the silicon wafer needs to be cleaned.

[0033] For cleaning, use high-purity deionized water with a resistivity greater than 18MΩ*cm to perform flow cleaning on the etched silicon wafer until the surface of the silicon wafer is clean.

technical field

[0001] The invention relates to the technical field of microelectronic processing, in particular to a semiconductor silicon wafer etching solution and an etching method thereof. Background technique

[0002] In the microelectronics processing technology, the semiconductor wafer manufacturing process generally includes the following steps: providing a wafer inverted garden obtained by cutting and slicing a single crystal block, mechanical polishing, etching, polishing and cleaning, and producing a wafer with high-precision flatness wafer. Wafers that have undergone mechanical treatments such as dicing, OD grinding, slicing, grinding, etc. have a damaged layer, that is, a process-damaged layer on one of its surfaces that causes slippage, dislocation, etc. during device fabrication Crystal defects reduce the mechanical strength of the wafer and adversely affect the electrical properties. Therefore, this layer must be completely removed. In order to remove the p...

Examples

Embodiment 1

[0017] A semiconductor silicon wafer etching solution is prepared by mixing 65% nitric acid, 45% hydrofluoric acid and 95% glacial acetic acid according to the volume ratio of 4:4:6.

[0018] The etching method for the semiconductor silicon wafer by the etching solution comprises placing the semiconductor silicon wafer in a closed container filled with the etching solution, and performing etching under low temperature conditions, and the low temperature is -12°C.

[0019] Inert gas nitrogen was passed into the container. The flow rate is 1 sccm.

[0020] After the semiconductor silicon wafer is etched, the silicon wafer needs to be cleaned.

[0021] For cleaning, use high-purity deionized water with a resistivity greater than 18MΩ*cm to perform flow cleaning on the etched silicon wafer until the surface of the silicon wafer is clean.

Embodiment 2

[0023] A semiconductor silicon wafer etching solution is prepared by mixing 70% nitric acid, 55% hydrofluoric acid and 99% glacial acetic acid according to the volume ratio of 14:14:18.

[0024] The method for etching semiconductor silicon wafers by the etching solution comprises placing the semiconductor silicon wafers in an airtight container filled with etching solutions, and performing etching under low temperature conditions, the low temperature being -8°C.

[0025] The container is filled with inert gas argon. The flow rate is 800 sccm.

[0026] After the semiconductor silicon wafer is etched, the silicon wafer needs to be cleaned.

[0027] For cleaning, use high-purity deionized water with a resistivity greater than 18MΩ*cm to perform flow cleaning on the etched silicon wafer until the surface of the silicon wafer is clean.

Embodiment 3

[0029] A semiconductor silicon wafer etching solution is prepared by mixing 66% nitric acid, 48% hydrofluoric acid and 97% glacial acetic acid according to the volume ratio of 6:6:8.

[0030] The etching method for the semiconductor silicon wafer by the etching solution comprises placing the semiconductor silicon wafer in an airtight container filled with the etching solution, and performing etching under low temperature conditions, the low temperature being -10°C.

[0031] The container is filled with inert gas helium. The flow rate is 500 sccm.

[0032] After the semiconductor silicon wafer is etched, the silicon wafer needs to be cleaned.

[0033] For cleaning, use high-purity deionized water with a resistivity greater than 18MΩ*cm to perform flow cleaning on the etched silicon wafer until the surface of the silicon wafer is clean.