Vertical memory devices including charge trapping patterns with improved retention characteristics

A vertical memory device includes a channel extending vertically on a substrate. A charge storage structure is disposed on a sidewall of the channel. Gate electrodes are spaced apart from each other vertically and surround the charge storage structure. A first insulation pattern includes an air gap between the gate electrodes. The charge storage structure includes a tunnel insulation layer, a charge trapping pattern, and a first blocking pattern sequentially stacked horizontally. The charge storage structure includes charge trapping patterns spaced apart from each other vertically. Each of the charge trapping patterns faces one of the gate electrodes horizontally. A length in the first direction of an outer sidewall of each of the charge trapping patterns facing the first blocking pattern is less than that of an inner sidewall thereof facing the tunnel insulation layer.