Patent ID: 8937021
Filing Date: 2015-01-20
Classification: H01L

Abstract:
1. A method of forming a three dimensional NAND structure atop a substrate, comprising: (a) providing to a process chamber a substrate having alternating nitride layers and oxide layers or alternating polycrystalline silicon consisting layers and oxide layers formed atop the substrate and a photoresist layer formed atop the alternating nitride layers and oxide layers or alternating polycrystalline silicon consisting layers and oxide layers; (b) etching the photoresist layer to expose at least a portion of the alternating nitride layers and oxide layers or alternating polycrystalline silicon consisting layers and oxide layers; (c) providing a process gas comprising sulfur hexafluoride (SF (d) providing an RF power of about 4 kW to about 6 kW to a first inductive RF coil and a second inductive RF coil disposed proximate the process chamber to ignite the process gas to form a plasma, wherein a current flowing through the first inductive RF coil is out of phase with RF current flowing through the second inductive RF coil; and (e) etching through a desired number of the alternating nitride layers and oxide layers or alternating polycrystalline silicon consisting layers and oxide layers to form a feature.