Patent ID: 9553100
Date: 2017-01-24
CPC Classifications: H01L

Claim:
1. A method of forming a three-dimensional memory device, comprising: forming a stack of alternating layers comprising first material layers and second material layers over a substrate; forming a memory opening through the stack; forming a memory film and a semiconductor channel in the memory opening; forming backside recesses by removing the second material layers selective to the first material layers and the memory film, wherein an outer sidewall of the memory film is physically exposed within each backside recess; forming a silicon-containing semiconductor portion over the memory film within each backside recess; converting an outer portion of each silicon-containing semiconductor portion into a dielectric material portion, wherein a remaining portion of each silicon-containing semiconductor portion constitutes a floating gate electrode for the three-dimensional memory device; and forming conductive material layers by depositing a conductive material within the backside recesses, wherein the step of forming the silicon-containing semiconductor portion over the memory film within each backside recess comprises: forming at least one set of surfaces selected from silicon deposition inhibiting surfaces on the first material layers and silicon deposition promoting surfaces over the memory film in the back side recesses; and selectively growing the silicon-containing semiconductor portions laterally within each backside recess.