Semiconductor structure with source and drain electrode embedded within semiconductor layer and manufacturing method thereof

A memory selector, comprising:

• a gate electrode embedded in a dielectric layer;
• a gate dielectric layer over the gate electrode;
• a semiconductor layer over the gate dielectric layer;
• a source electrode and a drain electrode horizontally aligned with the semiconductor layer and contacting the gate dielectric layer, wherein each of the source electrode and the drain electrode comprises a conductive material different from a material of the semiconductor layer;
• and
• a drain via electrically connecting the drain electrode to a memory element.

A semiconductor structure, comprising:

• a substrate;
• a transistor disposed over the substrate;
• and
• a memory element disposed over the transistor and electrically connected to the transistor,
• wherein the transistor comprises:
• a gate electrode;
• a source electrode and a drain electrode over the gate electrode;
• and
• a semiconductor layer, wherein the source electrode and the drain electrode are embedded within the semiconductor layer, and wherein each of the source electrode and the drain electrode comprises a conductive material different from a material of the semiconductor layer.