A device having thin-film transistor (TFT) silicon-aluminum oxide-silicon (SAS) memory cell structures is provided. The device includes a substrate, a dielectric layer on the substrate, and one or more source or drain regions being embedded in the dielectric layer. the dielectric layer being associated with a first surface. Each of the one or more source or drain regions includes an N+ polysilicon layer on a diffusion barrier layer which is on a conductive layer. The N+ polysilicon layer has a second surface substantially co-planar with the first surface. Additionally, the device includes a P− polysilicon layer overlying the co-planar surface, an aluminum oxide layer overlying the P− polysilicon layer; and at least one control gate overlying the aluminum oxide layer. In a specific embodiment, the control gate is made of highly doped P+ polysilicon. A method for making the TFT SAS memory cell structure is provided and can be repeated to integrate the structure three-dimensionally.