Copper etching method

Abstract

The invention discloses a copper etching method. The copper etching method comprises the steps of depositing a copper metal layer on a medium layer; forming a photoresist mask figure on the copper metal layer by utilizing a photolithography technology; utilizing the photoresist mask figure as a mask, etching the copper metal layer by using hydrogen, and forming an interconnection line figure; removing the photoresist mask figure. According to the copper etching method provided by the invention, gaseous copper hydride can be generated due to the reaction of the hydrogen in a plasma state with copper under a non-high-temperature situation, thus the copper etching method under a lower temperature is realized, and a non-high-temperature-resisting material can be prevented from being damaged by the high temperature etching; in addition, the etching on the medium layer is avoided, thus the problem in the prior art that a critical size is easily subjected to deviation caused by the damage to a low-k material and the consumption of methyl groups due to the etching on the medium layer can be avoided, and the problems in the prior art that the production difficulty and the production cost are increased due to the strict control on the critical size are avoided.

Description

Technical field [0001] The invention relates to semiconductor technology, in particular to a copper etching method. Background technique [0002] Since the advent of semiconductor integrated circuits, integrated circuit technology has developed rapidly, and each advancement and update of integrated circuit technology is marked by the reduction of the smallest feature size processed, the increase of silicon chip size, and the increase of chip integration. Among them, the reduction of feature size is the most critical. With the shrinking of feature size, the continuous improvement of packaging density and operating frequency, the cross-sectional area and line spacing of interconnect lines on the chip continue to decrease. With the advancement of integrated circuit technology, the increase in the interconnect delay of interconnect lines accounts for an increasing proportion of the integrated circuit system delay, which has become the main factor limiting the speed of the integrated...

AI Technical Summary

Problems solved by technology

[0007] The invention provides a copper etching method, which is used to solve the problems of increased production difficulty and increased production cost in the prior art due to the need to strictly control critical dimensions

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