BOE etching solution and preparation method thereof

By introducing a complex of benzotriazole-imidazolium-grafted polyethyleneimine and aminotrimethylenephosphonic acid into the BOE etching solution as a metal corrosion inhibitor, and using a composite buffer regulator of ammonium hydrogen fluoride, boric acid and amino acids, the problem of severe metal corrosion in the prior art is solved. This achieves efficient etching of silicon dioxide while reducing corrosion of metals such as tungsten, aluminum and titanium, thus meeting the high precision and high reliability requirements of advanced semiconductor devices.

CN122080937APending Publication Date: 2026-05-26SUZHOU BOYANG CHEM
5 Cites 0 Cited by

Patent Information

Application Number
CN202610559576.4
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2026-04-27
Publication Date
2026-05-26

AI Technical Summary

Technical Problem

Existing BOE etching solutions cannot effectively suppress metal corrosion when etching devices containing metals such as tungsten, aluminum, and titanium. This is especially true under conditions of open contact holes and slight over-etching, which can lead to thinning, denting, or even breakage of metal lines, failing to meet the requirements of high-precision and high-reliability processes.

Method used

A complex of benzotriazole-imidazolium grafted with polyethyleneimine and aminotrimethylenephosphonic acid is used as a metal corrosion inhibitor, combined with a composite buffer regulator of ammonium hydrogen fluoride, boric acid and amino acids to form a stable protective structure, ensuring the high etching activity of the etching solution on silicon dioxide, while reducing corrosion of the metal.

Benefits of technology

It achieves high etching rates for silicon dioxide and extremely low corrosion rates for metals such as tungsten, aluminum, and titanium, ensuring the structural integrity of the device and improving the stability of the etching solution and the electrical stability and long-term reliability of the device.

✦ Generated by Eureka AI based on patent content.
Patent Text Reader

Abstract

The invention relates to the technical field of etching solutions, and particularly discloses a BOE etching solution and a preparation method thereof. The BOE etching solution comprises the following raw materials: hydrofluoric acid, ammonium fluoride, a metal corrosion inhibitor, a composite buffer regulator, perfluorobutyl polyoxyethylene ether and ultrapure water, the metal corrosion inhibitor is a compound of benzotriazole-imidazole grafted polyethyleneimine and amino trimethylene phosphonic acid; the composite buffer regulator comprises ammonium bifluoride, boric acid and amino acid. The BOE etching solution can be used for the back-end metal wiring process of integrated circuits, MEMS devices, 3D NAND and the like, is especially suitable for silicon dioxide etching containing tungsten, aluminum and titanium metals, has high etching rate, low metal corrosion and excellent metal surface protection effect, and can effectively solve the technical problems that an existing BOE etching solution is serious in metal corrosion, and etching and protection are difficult to take into account at the same time.
Need to check novelty before this filing date? Find Prior Art