Reactive sputter etching of polysilicon utilizing a chlorine etch gas

摘要

In a chlorine plasma, reactive sputter etching of monocrystalline silicon, undoped polycrystalline silicon or doped polycrystalline silicon is achieved. The etching processes are substantially free of any loading effects and are characterized by high resolution, excellent uniformity and high selectivity with respect to, for example, silicon dioxide. For silicon and undoped polysilicon, the edge profile of the etched material is anisotropic. For doped polysilicon, the edge profile can be controlled to occur anywhere in the range from completely isotropic to completely anisotropic.