Electrostatic protection systems and methods
View Patent ↗Systems and methods are disclosed herein to provide improved electrostatic protection for electrical circuits. For example, in accordance with an embodiment of the present invention, an electrostatic protection device includes: a drain region formed in a substrate; a gate separated from the substrate by a gate oxide; and an isolation region formed in the substrate, the isolation region being adapted to isolate the gate oxide from a DC voltage coupled to the drain region.
1. An electrostatic protection device comprising:
a drain region formed in a substrate;
a gate separated from the substrate by a gate oxide; and
a shallow trench isolation region formed in the substrate and adjacent to the drain region, the isolation region being adapted to isolate the gate oxide from a DC voltage coupled to the drain region, wherein the isolation region does not extend under the gate.
2. The electrostatic protection device of claim 1 , wherein the drain region is at least as deep as the isolation region.
3. The electrostatic protection device of claim 1 , wherein the drain region is formed using a high dose implant.
4. The electrostatic protection device of claim 1 , wherein the electrostatic protection device is adapted to enter a snapback operation in response to coupling a source of electrostatic voltage to the drain region.
5. The electrostatic protection device of claim 1 , wherein:
the electrostatic protection device is adapted to enter a snapback operation in response to coupling a source of electrostatic voltage to the drain region; and
the gate is adapted to receive a control voltage to adjust a trigger voltage associated with the snapback operation.
6. The electrostatic protection device of claim 1 , wherein drain region comprises n-type material, and the substrate comprises p-type material.
7. The electrostatic protection device of claim 1 , wherein the drain region is coupled to a pad of an integrated circuit.
8. The electrostatic protection device of claim 1 , wherein the electrostatic protection device is provided in an integrated circuit.
9. The electrostatic protection device of claim 1 , wherein the electrostatic protection device is a transistor.
10. An electrostatic protection device comprising:
a drain region formed in a substrate;
a gate separated from the substrate by a gate oxide; and
a shallow trench isolation region formed in the substrate and adjacent to the drain region, the isolation region being adapted to isolate the gate oxide from a DC voltage coupled to the drain region, wherein the isolation region does not extend under the gate and is between the drain region and the gate oxide.
11. The electrostatic protection device of claim 10 , wherein the isolation region extends between the drain region and the gate oxide.