Post etch treatment (PET) of a low-K dielectric film

摘要

Post etch treatments (PETs) of low-k dielectric films are described. For example, a method of patterning a low-k dielectric film includes etching a low-k dielectric layer disposed above a substrate with a first plasma process. The etching involves forming a fluorocarbon polymer on the low-k dielectric layer. The low-k dielectric layer is surface-conditioned with a second plasma process. The surface-conditioning removes the fluorocarbon polymer and forms an Si—O-containing protecting layer on the low-k dielectric layer. The Si—O-containing protecting layer is removed with a third plasma process.

主权项

1. A method of patterning a low-k dielectric film, the method comprising:
etching a low-k dielectric layer disposed above a substrate with a first plasma process, the etching comprising forming a fluorocarbon polymer on the low-k dielectric layer; surface-conditioning, with a second plasma process, the low-k dielectric layer to remove the fluorocarbon polymer and to form an Si—O-containing protecting layer on the low-k dielectric layer, wherein surface-conditioning the low-k dielectric layer with the second plasma process comprises using a plasma derived from an oxygen radical source and a silicon source, and wherein the silicon source is a molecule that reacts with an oxygen radical to form a silicon oxide layer on the low-k dielectric layer, the silicon source selected from the group consisting of silicon tetrafluoride (SiF4), silicon tetrachloride (SiCl4), silane (SiH4) dimethylsilane ((CH3)2SiH2), trimethylsilane ((CH3)3SiH), and N -(Trimethylsilyl)dimethylamine ((CH3)3SiN(CH2)2); and removing the Si—O-containing protecting layer with a third plasma process.