Example embodiments relate to methods for forming a stacked FET device. An example method includes forming a bottom FET device that includes a source, a drain, at least one channel layer between the source and drain, and a bottom gate electrode arranged along the at least one channel layer. The method also includes forming a bonding layer over the bottom FET. Additionally, the method includes forming a top FET device on the bonding layer. Forming the top FET device includes forming a device layer structure. The device layer structure includes at least one channel layer of a channel semiconductor material and a top sacrificial layer of a sacrificial semiconductor material. Further, the method includes replacing the top sacrificial layer with a dummy layer of a dielectric dummy material, forming a gate-to-gate contact trench, depositing gate electrode material, and forming a source and a drain of the top FET device.