Electrically programmable antifuses and methods for forming the same

A one time, voltage programmable logic element in a semiconductor substrate of first conductivity type comprising:

• a first layer formed in a surface of the substrate, the first layer having a second conductivity type;
• and
• a trench formed through the surface and passing through the first layer, the trench comprising:
• an interior surface;
• a first dielectric material lining the interior surface of the trench;
• and
• a second dielectric material filling the lined trench;
• a dielectric layer formed over a portion of the first layer and contacting the first dielectric material lining the trench at a merge location;
• an electrode extending over a portion of both the dielectric layer and the filled trench;
• and
• a contact structure provided over a portion of the first layer, contacting the dielectric layer, and being electrically isolated from said electrode so as to provide electrical contact thereto said first layer,
• wherein the logic element is configured so that a predetermined voltage or higher applied between the electrode and the first layer causes a breakdown near the merge location.

A MOSFET structure comprising:

• a one time, voltage programmable logic element in a semiconductor substrate of first conductivity type comprising:
• a first layer formed in a surface of the substrate, the first layer having a second conductivity type;
• and
• a trench formed through the surface and passing through the first layer, the trench comprising:
• an interior surface;
• a first dielectric material lining the interior surface of the trench;
• and
• a second dielectric material filling the lined trench;
• a dielectric layer formed over a portion of the first layer and contacting the first dielectric material lining the trench at a merge location;
• an electrode extending over a portion of both the dielectric layer and the filled trench,
• a contact structure provided over a portion of the first layer, contacting the dielectric layer, and being electrically isolated from said electrode so as to provide electrical contact thereto said first layer
• wherein the logic element is configured so that a predetermined voltage or higher applied between the electrode and the first layer causes a breakdown near the merge location;
• a source diffusion region of the first conductivity type formed within the first layer;
• and
• a drain diffusion region of the first conductivity type formed within the first layer.

A one time, voltage programmable logic element in a semiconductor substrate of first conductivity type comprising:

• a first layer beneath a surface of the substrate, the first layer having a second conductivity type;
• a trench formed through the surface and passing through the first layer, the trench comprising:
• an interior surface;
• a dielectric material lining the interior surface of the trench;
• and
• a conductive material filling the lined trench;
• and
• a second layer beneath the surface of the substrate, coupled to the first layer and surrounding the trench, the second layer having the second conductivity type,
• wherein the logic element is configured so that a predetermined voltage or higher applied between the conductive material and the first layer causes a breakdown within a region of the trench.