Etching liquid used for thick aluminum circuit board, and method

Abstract

The invention provides etching liquid used for a thick aluminum circuit board, and a method. The etching liquid comprises the following main ingredients: concentrated hydrochloric acid, acetic acid, hydrofluoric acid and the balance of aluminum ions. The method specifically comprises the following steps that: laminating one surface of an aluminum foil with one layer of protection film, and laminating the other surface of the aluminum foil with a dry film; according to a preset condition, carrying out selective exposure on different positions of the dry film, removing the dry films on unexposedpositions to expose the aluminum foils under the dry films; and dissolving through the etching liquid to remove the exposed aluminum foils, and removing the dry films on the aluminum foils to obtainthe etched thick aluminum circuit board which needs to be prepared. By use of the etching liquid formed by hydrochloric acid, phosphoric acid, acetic acid and hydrofluoric acid at a certain ratio, thick aluminum etching can be realized, in addition, the acetic acid and the phosphoric acid added in the etching liquid can effectively improve the linearity of the circuit, the etching factor of the circuit is improved through the added hydrofluoric acid, an etching rate is stabilized through added aluminum chloride or dissolved aluminum, and therefore, thick aluminum etching meets use requirements.

Description

Technical field: [0001] The invention relates to the technical field of circuit board manufacturing, in particular to an etching solution and method for thick aluminum circuit boards. Background technique: [0002] In order to improve the safety, convenience, comfort and intelligence of automobiles, electronic systems are widely used in automobiles, such as radar, stereo camera, infrared monitoring, car audio, Internet and navigation, etc. With the country's advocacy and support for new energy vehicles and smart vehicles in recent years, the demand for circuit boards in automotive electronic components will usher in a new growth point with the outbreak of automotive electronics. Automotive electronic systems have relatively high reliability requirements for circuit boards, which must be able to operate normally within the life cycle and withstand the test of the natural environment during use. At present, a large number of automotive circuit boards on the market use copper f...

AI Technical Summary

Problems solved by technology

[0003] At present, other industries use metal aluminum as the line conductor, but the thickness of the aluminum foil in this industry is relatively thin, about 10 to 30 microns. The current requires the thickness of aluminum to reach about 100 microns. It is difficult to make lines with a line width / line spacing of 200 microns / 200 microns with ordinary etching potions for etching aluminum.

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