Deep trench capacitor including stress-relief voids and methods of forming the same

A semiconductor structure comprising a first semiconductor die, wherein:

• the first semiconductor die comprises a semiconductor substrate and a deep trench capacitor embedded within the semiconductor substrate;
• and
• the deep trench capacitor comprises:
• at least one deep trench extending downward from a top surface of the semiconductor substrate;
• a layer stack including at least three metallic electrode layers interlaced with at least two node dielectric layers and continuously extending over the top surface of the semiconductor substrate and into each of the at least one deep trench;
• and
• a dielectric fill material layer including a vertically-extending portion that is located within one of the at least one deep trench, is laterally surrounded by the layer stack, and encapsulates a void of which an entire volume is free of any solid phase material such that all surfaces of the void within the dielectric fill material layer are surfaces of the dielectric fill material layer.

A device structure comprising:

• first deep trenches laterally extending along a first horizontal direction and vertically extending downward into a substrate from a top surface of the substrate;
• second deep trenches laterally extending along a second horizontal direction and vertically extending downward into the substrate from the top surface of the substrate;
• a layer stack including at least three metallic electrode layers interlaced with at least two node dielectric layers and continuously extending over the top surface of the substrate and into each of the first trenches and the second trenches;
• and
• a dielectric fill material layer comprising a dielectric fill material and including a horizontally-extending portion that overlies a topmost surface of the layer stack and a plurality of vertically-extending portions that extend downward from the horizontally-extending portion into a center region of a respective one of the first deep trenches and the second deep trenches and encapsulate a respective void of which an entire volume is free of any solid phase material such that all surfaces of each void within the dielectric fill material layer are surfaces of the dielectric fill material layer.