Patent ID: 9165786
Filing Date: 2015-10-20
Classification: H01L

Abstract:
1. A method of forming a 3-d flash memory cell, the method comprising: transferring a patterned substrate into a substrate processing mainframe, wherein the patterned substrate comprises a vertical stack of alternating silicon oxide and silicon nitride slabs surrounding a vertical memory hole and a conformal ONO layer overlying the vertical stack, wherein the conformal ONO layer comprises a first silicon oxide layer, a silicon nitride layer and a second silicon oxide layer; transferring the patterned substrate into a first substrate processing chamber mounted on the substrate processing mainframe; flowing a first fluorine-containing precursor into a first remote plasma region within the first substrate processing chamber while striking a plasma to form first plasma effluents from the fluorine-containing precursor; flowing the first plasma effluents into a first substrate processing region within the first substrate processing chamber; wherein the first substrate processing region houses the patterned substrate; reacting the first plasma effluents with the conformal ONO layer to etch back the first silicon oxide layer and the second silicon oxide layer within the vertical memory hole; transferring the patterned substrate without breaking vacuum from the first substrate processing chamber to a second substrate processing chamber mounted on the substrate processing mainframe; flowing a second fluorine-containing precursor and an oxygen-containing precursor into a second remote plasma region within the second substrate processing chamber while striking a plasma to form second plasma effluents and flowing the second plasma effluents through a showerhead into a second substrate processing region housing the patterned substrate within the second substrate processing chamber; reacting the second plasma effluents with the conformal ONO layer to etch back the silicon nitride layer; and removing the patterned substrate from the substrate processing mainframe.