Contact hole cleaning method and semiconductor structure

By forming a polysilicon hard mask layer above the metal gate in the semiconductor manufacturing process and cleaning the contact holes with SC1 solution, the problem of high contact resistance is solved, and effective removal of residues at the bottom of the contact holes and protection of the metal gate is achieved.

CN119725080APending Publication Date: 2025-03-28NEXCHIP SEMICON CO LTD
9 Cites 0 Cited by

Patent Information

Application Number
CN202510228839.9
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-02-28
Publication Date
2025-03-28

AI Technical Summary

Technical Problem

In semiconductor manufacturing processes, the contact resistance of the contact hole is large or unstable, mainly because the residual oxide or polymer at the bottom of the hole cannot be effectively removed, and the commonly used wet cleaning methods will damage the metal gate structure.

Method used

By forming a polysilicon hard mask layer above the metal gate and cleaning with a set concentration of SC1 solution when cleaning the contact holes, the wet cleaning solution is prevented from directly contacting the metal gate, thereby protecting the metal gate structure.

Benefits of technology

Without damaging the metal gate structure, the oxide or polymer residue at the bottom of the contact hole is effectively removed, the contact resistance is reduced, and the performance and yield of semiconductor devices are improved.

✦ Generated by Eureka AI based on patent content.
Patent Text Reader

Abstract

The invention discloses a contact hole cleaning method and a semiconductor structure, and the method comprises the steps: providing a semiconductor structure which comprises at least one metal gate structure; etching a metal gate in the metal gate structure by adopting an SC1 solution with a set concentration based on a set etching height; depositing polycrystalline silicon in the etched region in the metal gate structure to form a polycrystalline silicon hard mask layer; forming contact holes in the semiconductor structure, wherein the bottom of at least one contact hole is the top of the polycrystalline silicon hard mask layer; and cleaning the oxide and / or the polymer in the contact hole based on a set solution. Compared with the prior art, the unexpected technical effect of the invention is that residues at the bottom of the contact hole can be cleaned on the premise that the metal gate structure is not damaged.
Need to check novelty before this filing date? Find Prior Art