Processing technology of touch screen leading wire

Abstract

The invention relates to the technical field of touch screen leading wire processing, and particularly relates to a processing technology of a touch screen leading wire. The processing technology comprises the following steps of sequentially sputtering a Mo bottom layer, an Al middle layer and a Mo surface layer on a glass substrate by using argon as protective gas, and controlling the thickness of the Mo bottom layer to 300-400 angstroms, the thickness of the Al middle layer to 2400-2600 angstroms and the thickness of the Mo surface layer to 400-500 angstroms; then carrying out primary etching by using a phosphoric acid-sulfuric acid-nitric acid system etching liquid, wherein sulfuric acid has a certain passivation effect on the Al layer and slows downs the etching speed of the Al layer, and carrying out secondary etching by using a phosphoric acid-sodium acetate-nitric acid system etching liquid, wherein sodium acetate has the effect of a buffering agent, so that the etching speed of the Al layer is controlled. The processing technology is simple; and only two etching liquids are used for etching twice so as to ensure that the fracture surface of the etched Mo-Al-Mo touch screen leading wire is of a sloping structure.

Description

technical field [0001] The invention relates to the technical field of processing touch screen leads, in particular to a processing technology for touch screen leads. Background technique [0002] In the touch screen manufacturing process, Mo-Al-Mo is usually used as the edge lead (the upper and lower Mo layers respectively protect the Al layer and increase the adhesion) to connect the vertical and horizontal electrodes with the FPC. In the production process, the bottom Mo layer, the middle Al layer and the surface Mo layer are usually sequentially sputtered on the glass substrate, and the sputtering system is usually argon as the protective gas; then the sputtered Mo-Al-Mo layer is Etching to obtain the corresponding Mo-Al-Mo touch screen leads, and finally sputtering an ITO layer on it. Practice has proved that if the etched Mo-Al-Mo section is slope-shaped, that is, the bottom Mo layer extends out of the middle Al layer at the etched section of the Mo-Al-Mo layer on th...

AI Technical Summary

Problems solved by technology

[0003] However, in the actual process, since the etching rate of Al by common etchant is faster than that of Mo, the result of such etching is that Mo protrudes and Al recesses, often the middle Al layer is etched more, while the bottom layer and Al layer are etched more. The Mo on the surface is less etched, and the undercut phenomenon is easy to appear at the cross section

In this way, on the one hand, the edge of the Al in the concave part of the cross-section is likely to remain etching solution, which is easy to further corrode the Al layer, reducing the reliability of the final device and shortening its life; When ITO is plated on the Mo-Al-Mo layer, due to the depression of the Al layer at the cross-section, the sufficient contact between the Al layer and the ITO layer cannot be guaranteed, and it is easy to form an open circuit.