A kind of silicon etching liquid and its production process

Abstract

The invention discloses a silicon corrosion solution, which comprises the following raw materials in parts by weight: 8-12 parts of hydrofluoric acid, 70-78 parts of nitric acid, 15-25 parts of deionized water and 6-13 parts of composite corrosion inhibitor. And the present invention utilizes pyridine-4-formaldehyde as a substrate, and it reacts step by step with toluene, potassium permanganate, diethylenetriamine, and thiourea to form a composite corrosion inhibitor; the composite slow-release agent passes through the nitrogen in the molecule The large π bonds of atoms, sulfur atoms, and molecular structures form coordination bonds or chemical covalent bonds with metals, forming a dense hydrophobic film on the metal surface, which hinders the corrosion of metals by hydrogen ions in the solution, but the compound slows The nitrogen atoms, sulfur atoms, and large π bonds in the molecular structure in the release agent cannot form a coordination bond or a covalent bond with silicon, and cannot form a protective film on the silicon surface, which does not affect the corrosion behavior of the etching solution on silicon. Silicon etch is efficient, while metal etch is ineffective.

Description

technical field [0001] The invention belongs to the technical field of silicon processing, and in particular relates to a silicon etching solution and a production process thereof. Background technique [0002] In the semiconductor industry, silicon etching solution is usually used to process silicon to form a unique silicon structure to meet its application in semiconductors. However, the existing silicon etching solution is usually composed of hydrofluoric acid-nitric acid (HF-HNO 3 ) system, under normal circumstances, the volume ratio of hydrofluoric acid and nitric acid in this system is 1:8 or higher to obtain a strong enough oxidizing ability, and acetic acid is added as a buffer at the same time. This solution has a fast corrosion rate and is widely used. However, when this corrosive solution is used, the metal wires on the substrate are corroded at the same time, resulting in defective or even unqualified substrates. [0003] Therefore, it is necessary to provide...

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Problems solved by technology

However, when this corrosive solution is used, the metal wires on the substrate are corroded at the same time, resulting in defective or even unqualified substrates.

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