74results about How to "Guaranteed area" patented technology

The present application discloses a 3D memory device and a manufacturing method thereof. The manufacturing method comprises: forming a stop layer and a sacrificial layer on a substrate having a plurality of grooves, each groove being filled with the sacrificial layer, and the substrate and the sacrificial layer being separated by the stop layer; forming a stacked structure on the sacrificial layer; forming a channel column passing through the stacked structure, the channel column extending toward the substrate, the sidewall of the channel column contacting the sacrificial layer, and the channel column including a channel layer; forming a plurality of gate line gaps, each of which extends toward the substrate into the sacrificial layer; sequentially removing the sacrificial layer and the stop layer through the plurality of gate line gaps, so as to form a first gap between the stacked structure and the substrate, and part of the sidewall of the channel column being exposed by the first gap; removing part of the sidewall of the channel column through the first gap, so that part of the channel layer is exposed; and forming an epitaxial layer in the first gap, the channel layer being electrically connected to the substrate through the epitaxial layer, and each gate line gap corresponding to the position of the corresponding groove.