Deep trench electrostatic discharge (ESD) protect diode for silicon-on-insulator (SOI) devices

A method of forming a semiconductor structure including an electrostatic discharge (ESD) protect diode, the method comprising:

• forming an buried insulator layer on a bulk substrate of a first polarity type;
• forming an active semiconductor layer having a shallow trench isolation region and a diffusion region of the first polarity type on top of the buried insulator layer;
• forming a band region of a second polarity type within the bulk substrate and directly beneath the buried insulator layer to form a conductive path;
• forming a well region of the second polarity type in the bulk substrate and in contact with the band region;
• etching a deep trench through the active semiconductor layer, the buried insulator layer and the well region;
• blocking oxide formation within the deep trench;
• filling the deep trench with a conductive material of the first polarity type, and defining the ESD protect diode at a junction between a lower portion of the deep trench and the well region.