Abstract: Embodiments herein describe techniques for a thin-film transistor (TFT), which may include a substrate oriented in a horizontal direction and a transistor above the substrate. The transistor includes a gate electrode above the substrate, a gate dielectric layer around the gate electrode, and a channel layer around the gate dielectric layer, all oriented in a vertical direction substantially orthogonal to the horizontal direction. Furthermore, a source electrode or a drain electrode is above or below the channel layer, separated from the gate electrode, and in contact with a portion of the channel layer. Other embodiments may be described and/or claimed.