Vertically stacked fefets with common channel

Abstract

Ferroelectric field effect transistors are in a three-dimensional structure that includes vertical columns. Source/drain electrodes are provided by horizontal conductive layers that are interleaved with dielectric layers. Channels for the FeFETs in each vertical column are provided by a continuous semiconductor layer, e.g., a vertical strip of semiconductor. Another vertical strip may provide the ferroelectric layers for the FeFETs in the vertical column. The gate electrodes are provided by a control gate structure that connects the gate electrodes in parallel. The source/drain electrodes of multiple vertical columns may be connected in parallel. The source/drain electrodes of multiple tiers may also be connected in parallel. This structure provides high area density, adds an extra degree of freedom in circuit design, and lends itself to the use of oxide semiconductor channels.