Method of forming deep trench capacitor

A method of forming a deep trench capacitor structure, comprising:

• forming a deep trench within a semiconductor substrate;
• depositing a first nitride liner within the deep trench;
• filling a lower portion of the deep trench with an oxide material, wherein the lower portion of the deep trench overlaps at least a portion of a buried oxide (BOX) layer;
• depositing a second nitride liner within an upper portion of the deep trench, such that the second nitride liner is deposited over a top surface of the oxide material and over the first nitride liner along a pair of sidewalls of the deep trench within the upper portion of the deep trench;
• removing the oxide material, such that the lower portion of the deep trench includes only the first nitride liner and the upper portion of the deep trench includes the first nitride liner and the second nitride liner;
• forming a high doped region around the lower portion of the deep trench;
• and
• removing the first nitride liner within the lower portion of the deep trench and the second nitride liner within the upper portion of the deep trench.

A deep trench capacitor structure, comprising:

• a buried oxide (BOX) layer positioned atop a semiconductor substrate;
• a silicon-on-insulator (SOI) layer positioned atop the BOX layer;
• and
• a deep trench within the SOI layer, the BOX layer, and the semiconductor substrate, the deep trench including:
• an upper portion including the SOI layer and a least a portion of the BOX layer;
• and
• a lower portion including the semiconductor substrate and a remaining portion of the BOX layer,
• wherein the upper portion includes a first liner and a second liner along a pair of sidewalls of the upper portion of the deep trench and the lower portion includes only the first liner along a pair of sidewalls of the lower portion of the deep trench.