A semiconductor device includes a first stack of layers stacked on a substrate. The first stack of layers includes a source connection layer that is formed by replacing source sacrificial layers. The semiconductor device includes a channel structure that extends in the first stack of layers. The channel structure includes a channel layer that is in contact with the source connection layer in the first stack of layers. Further, the semiconductor device includes a shield structure formed in the first stack of layers. The shied structure encloses a stack of layers without the source connection layer.