Phosphoric acid based etching liquid and method for preparing same

Abstract

The invention relate to phosphoric acid based etching liquid with high etching selectivity and a method for preparing the phosphoric acid based etching liquid. The phosphoric acid based etching liquidwith the high etching selectivity mainly comprises, by weight, 50-90% of phosphoric acid, 0.005-1% of silicon-containing compounds, 0.005-1% of fluorine-containing compounds, 0.005-1% of fluorine stabilizers, 0.005-5% of surfactants and the balance water. The phosphoric acid based etching liquid and the method have the advantages that components and the types of novel additives and novel stabilizers are used, accordingly, SiO2 layer etching of the phosphoric acid based etching liquid can be obviously reduced, the Si3N4 layer etching speeds of the phosphoric acid based etching liquid can be obviously increased, and the Si3N4 / SiO2 etching selectivity can be obviously improved.

Description

technical field

[0001] The invention belongs to the field of electronic chemicals, in particular to a phosphoric acid-based etchant with high etching selectivity and a preparation method thereof. Background technique

[0002] With the development of technology, the way we generate data has undergone a great transformation. Before 2000, the Internet was the main source of data, but after 2017, the Internet of Things, smart cars, games, and VR will generate a large amount of data. According to the forecast of "Data Age 2025", the global data The volume will reach 163ZB, which is 10 times the current amount. Data needs to be stored in memory, and planar NAND flash memory is approaching its actual expansion limit, which poses severe challenges to the semiconductor memory industry.

[0003] The new 3D NAND technology stacks multiple layers of data storage cells vertically with excellent precision. This technology can support higher storage capacity in a smaller space. Compared...

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