Method for reducing defects on aluminum gasket surface

Abstract

The invention discloses a method for reducing defects on an aluminum gasket surface. According to the method for reducing the defects on the aluminum gasket surface, an aluminum gasket is divided into two layers and the two layers are respectively deposited. According to first layer aluminum deposition, a thin aluminum layer grows at a low temperature through the method of magnifying target direct current power. Second layer aluminum deposition grows at a high temperature. Due to low reaction temperature, a first aluminum layer is small in grains and smooth in surface, a surface medium layer is effectively controlled, the surface medium layer is easily etched and removed during a follow-up forming process of a metal wire graph, meanwhile, the direct current power is magnified when the aluminum layer grows at the lower temperature, sputtered aluminum ions have large motion energy, and therefore good passivation layer step covering capacity is achieved. When the second aluminum layer grows at high-temperature environment, due to cooling buffering time, temperature of wafer surfaces drops, and due to the fact that the first aluminum layer at the lower layer of the second aluminum layer is smooth in surface, stress can be released easily, and beard-shaped defects are reduced.

Description

Technical field [0001] The invention relates to a process method for producing an aluminum liner, in particular to a method for reducing surface defects of the aluminum liner. Background technique [0002] In the semiconductor manufacturing process, in the subsequent passivation layer process, a layer of aluminum pad is needed, formed on the upper end of the metal interconnection layer, as a lead terminal for testing electrical connections and packaging. [0003] At present, the industry manufacturing aluminum pads generally use process methods such as figure 1 As shown, where: 201 is a semiconductor substrate, the surface of the substrate is a metal interconnection layer, and 202 is a passivation layer. The passivation layer is generally composed of silicon oxide, silicon nitride, silicon oxynitride, etc., to prevent the diffusion of the substrate metal The barrier layer 203 is an aluminum layer, and the deposited aluminum is connected to the metal layer in the passivation layer t...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that the step coverage ability of aluminum metal is not good, and the aluminum layer grown at room temperature cannot cover the passivation layer with steps well, resulting in voids, peeling and affecting electrical properties, which limit range of applications

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