| 摘要 |
A method of etching TiSix is provided, wherein the surface of the TiSix (110) is exposed, typically through a patterned mask, to a plasma etchant. The plasma etchant comprises (i) at least one fluorine containing gas, such as SF6, NF3, CxFy (where x ranges from about 1 to about 10), and compatible mixtures of such gases; and (ii) a gas selected from the group consisting of HBr, Cl2, and combinations thereof. Conventional methods of etching TiSix use Cl2 or HBr as the plasma etchant. However, these methods can lead to undesirable residues (150), due to the presence of silicon nodules (140) in the present TiSix. The present invention overcomes the residue problem by adding a fluorine containing gas to the plasma etchant, which is then able to effectively etch the Si nodules (140) at an etch rate which is approximately the same as the etch rate of the TiSix (110), so that the undesirable residue is not formed. |
