METHOD OF FORMING THE GATE WITH THE LELE DOUBLE PATTERN

摘要

The invention relates to microelectronic technology and, more specifically, relates to a method of forming a gate with a LELE double pattern. The method adopts an ONO structure (Oxide-SiN-Oxide). The ONO structure is exposed twice, and the advanced patterning film is used as a mask in the processing of polysilicon etching. The ONO structure is used to replace the traditional hardmask of silicon oxide, and the substructure of ODL (Organic Under Layer) which is based on the spin-on, and the middle layer structure of SHB (Si-based hardmask). The method saves cost and improves the process of advanced patterning film as a mask with the nodes in 40 nm and above which is applied to the process with the nodes in 22/20 nm and below. Consequently, the maturity and stability of the process for poly gate with the nodes in 22/20 nm and below are improved.