Self-aligned double patterning method

Abstract

The invention provides a self-alignment double patterning method. The method comprises the steps of forming a silicon-containing filling material layer, an anti-reflection layer and a photoresist pattern on a to-be-etched layer; taking the photoresist pattern as a mask, etching the silicon-containing filling material layer and carrying out heat treatment on the silicon-containing filling materiallayer to shrink the silicon-containing filling material pattern so as to form a silicon dioxide pattern; depositing an etching mask layer and performing back etching, and forming a side wall on the side wall of the silicon dioxide pattern; removing the silicon dioxide pattern; and etching the to-be-etched layer to form a target pattern. According to the invention, the characteristic that the silicon-containing filling material shrinks after high-temperature heat treatment is utilized to obtain a smaller pattern spacing compared with the traditional self-alignment double patterning process, sothat the miniaturization of a semiconductor device is facilitated; and the characteristic that the silicon-containing filling material generates silicon dioxide after high-temperature heat treatment is utilized, and the silicon-containing filling material can be used as a sacrificial layer in a self-alignment double patterning method, so that the steps of growing, etching and removing the sacrificial layer in the traditional process are omitted, the process flow is simplified, and the cost is saved.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a method for self-alignment double patterning. Background technique [0002] The increasing integration of semiconductor devices is driving the technology nodes of the semiconductor manufacturing process forward. For the technology nodes of 14nm and below, the single-patterning technology using the deep ultraviolet (DUV) lithography process can no longer meet the requirements. , but must use extreme ultraviolet (EUV) lithography process or double patterning (Double Patterning) technology, and as a kind of double patterning technology, self-aligned double patterning (Self-aligned Double Patterning, SADP) technology uses only one light Compared with the traditional double patterning technology, the photolithography process is used once less, which has a certain cost advantage. Therefore, the self-aligned double patterning technology is gradually being adopted by the industry...

AI Technical Summary

Problems solved by technology

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method for self-aligned double patterning, which is used to solve the problem of high requirements on photolithography process and complex process in the prior art when the pattern is miniaturized

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