Cleaning reagent and manufacturing process of aluminum pad

Abstract

The invention provides a manufacturing process of an aluminum pad, which comprises the steps of providing a semiconductor substrate, wherein a metal interconnection line is arranged on the active surface of the semiconductor substrate; sequentially forming an etch stop layer and a first insulating material layer on the semiconductor substrate; etching the first insulating material layer and the etch stop layer, and forming an opening in the position which corresponds to the metal interconnection line; forming a metal aluminum layer in the opening and on the first insulating material layer; removing the metal aluminum layer on the first insulating material layer, and forming the aluminum pad which is electrically connected with the metal interconnection line; forming a second insulating material layer on the first insulting material layer; and cleaning the aluminum pad, wherein cleaning liquid for cleaning the aluminum pad contains 3-10% of H2SO4, 5-20% of H2O2 and the balance of H2O according to the volume percent. The method can prevent the corrosion of the aluminum pad after cleaning.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a cleaning agent and a manufacturing process of an aluminum pad. Background technique [0002] With the further shrinking of the feature size of semiconductor devices, the RC delay of the interconnection line has gradually become the main contradiction affecting the circuit speed. In order to improve this, the process method of making the metal interconnection line structure from metal copper has been adopted. Compared with the traditional aluminum process, the advantage of the copper process is that it has lower resistivity and better conductivity, and the interconnection wires made of it can be made smaller while maintaining the same or even stronger current carrying capacity. more dense. In addition, it also has greater advantages over aluminum processes in terms of electromigration, RC delay, reliability, and lifetime. As for the pad structure (pad) connected to it, ...

AI Technical Summary

Problems solved by technology

The process of forming the aluminum pad generally includes: providing a semiconductor substrate 100 with a metal interconnection line 110 on the active surface of the semiconductor substrate 100; forming an etching stopper layer 130 and a second An insulating material layer 140; etching the first insulating material layer 140 and the etching barrier layer 130 to form an opening at a position corresponding to the metal interconnection line; forming a metal in the opening and on the first insulating material layer 140 Aluminum layer; remove the metal aluminum layer on the first insulating material layer to form an aluminum pad 120 electrically connected to the metal interconnection line; subsequently, form a second insulating layer on the first insulating material layer and the aluminum pad 120 material layer 150, and spray photoresist on the second insulating layer 150, and remove the photoresist on the aluminum pad by exposing and developing processes, leaving only the second insulating layer on the first insulating layer, and finally , using an ashing process to remove the photoresist on the second insulating layer. In the ashing process, metal polymers will be generated on the surface of the aluminum pad and the second insulating layer. Therefore, cleaning is required. The cleaning process used Detergents usually contain H 2 SO 4 , H 2 O, HF, with the described cleaning reagents, after cleaning the aluminum pads, corrosion of the aluminum pads usually occurs, which can lead to failure of the aluminum pad leads

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