Integrated circuit electrical protection device
An integrated circuit electrical protection device includes a semiconductor substrate, and first, second, and third doped regions of a first polarity in the semiconductor substrate. The first and second doped regions are separated from one another by a first body region having a second polarity and the second and third doped regions are separated from one another by a second body region having the second polarity. The first and second polarities are different from one another. A fourth doped region of the second polarity directly abutting and in contact with the third doped region. A first gate structure is formed over the first body region between the first and second doped regions. A second gate structure is formed over the second body region between the second and third doped regions.
1. An integrated circuit electrical protection device comprising:
a semiconductor substrate;
first, second, and third doped regions of a first polarity in the semiconductor substrate, wherein the first and second doped regions are separated from one another by a first body region having a second polarity in the semiconductor substrate and the second and third doped regions are separated from one another by a second body region having the second polarity in the semiconductor substrate, wherein the first and second polarities are different from one another, and wherein the first body region has an electric potential;
a fourth doped region of the second polarity in the semiconductor substrate, wherein the fourth doped region directly abuts and is in contact with the third doped region;
a first gate structure formed on the semiconductor substrate over the first body region between the first and second doped regions; and
a second gate structure formed on the semiconductor substrate over the second body region between the second and third doped regions, the second gate structure having an active state such that when the second gate structure is in the active state, the electric potential is controlled by a conductive path between the first body region and the second doped region through the substrate via the third and fourth doped regions and a conductive channel in the second body region.
2. The device of claim 1 , further comprising:
a layer of conductive material over the third and fourth doped regions and electrically coupling the third doped region to the fourth doped region.
3. The device of claim 1 , having a further characterization comprising:
one of a group consisting of:
the first doped region is a source and the second doped region is a drain, and
the first doped region is a drain and the second doped region is a source.
4. The device of claim 1 , wherein:
the first polarity is an N polarity; and
the second polarity is a P polarity, wherein when the second gate structure is activated, the electric potential in the first body region is elevated.
5. The device of claim 1 , wherein:
the first polarity is an N polarity;
the second polarity is a P polarity, wherein when the second gate structure is activated, the electric potential in the first body region is maintained at a low voltage potential.
6. The device of claim 1 , wherein the first and second gate structures are driven to a same logic level.
7. The device of claim 1 , wherein the first gate structure is driven to a first logic level and the second gate structure is driven to second logic level that is opposite the first logic level.
8. The device of claim 1 , further comprising a trigger circuit configured to detect electrical overstress events and to control the first and second gate structures.
9. The device of claim 1 , further comprising a resistor coupled between the first doped region and the first body region.
10. The device of claim 1 , further comprising a fifth doped region of the second polarity that couples the first body region to the first doped region via the substrate.
11. The device of claim 1 , wherein the first doped region is coupled to a first voltage supply rail and the second doped region is coupled to a second voltage supply rail.
12. A voltage protection device, comprising:
a semiconductor substrate;
a first metal oxide semiconductor field effect transistor (MOSFET) including a first doped region and a second doped region formed in the semiconductor substrate and a first gate structure formed over a first body region of the semiconductor substrate between the first and second doped regions, wherein the first body region has an electric potential;
a fourth doped region in the semiconductor substrate formed directly adjacent to and in contact with the third doped region, wherein the fourth doped region has a first polarity that is different than a second polarity of the first, second and third doped regions; and
a second MOSFET including the second doped region and a third doped region formed in the semiconductor substrate and a second gate structure formed over a second body region of the semiconductor substrate between the second and third doped regions; the second MOSFET having a conductive state such that when the MOSFET is in the conductive state, the electric potential is controlled by a conductive path between the first body region and the second doped region through the substrate via the second MOSFET, the third doped region, and the fourth doped region.
13. The device of claim 12 , wherein:
the first polarity is an N polarity;
the second polarity is a P polarity, wherein when the second MOSFET is in conductive mode, the electric potential in the first body region is elevated.
14. The device of claim 12 , wherein:
the first polarity is an N polarity;
the second polarity is a P polarity, wherein when the second MOSFET is in conductive mode, the first body region is maintained at a low voltage potential.
15. The device of claim 12 , further comprising a further characterization of a group consisting of:
the first and second gate structures are driven to a same logic level; and
the first gate structure is driven to a first logic level and the second gate structure is driven to second logic level that is opposite the first logic level.
16. The device of claim 12 , further comprising a resistor coupled between the first doped region and the first body region, wherein the first doped region is coupled to a first voltage supply rail and the second doped region is coupled to a second voltage supply rail.
17. The device of claim 12 , further comprising a fifth doped region of the second polarity that couples the first body region to the first doped region via the substrate.
18. A method of making of operating an integrated circuit device having first and second MOSFETs using a substrate, comprising:
controlling a first gate structure of the first MOSFET and a second gate structure of the second MOSFET to control a voltage potential in a first body region of the integrated circuit device by coupling a first body region of the first MOSFET to a second doped region through the substrate via the second MOSFET, a third doped region, and a fourth doped region, wherein
the first gate structure and the first and second doped regions are part of the first MOSFET,
the second gate structure and the second and third doped regions are part of the second MOSFET,
the fourth doped region is positioned directly in contact with the third doped region, and
a polarity of the first, second, and third doped regions is opposite a polarity of the fourth doped region.
19. The method of claim 18 , wherein:
the controlling the first and second gate structures changes the voltage potential of the first body region in response to an overstress event.
20. The method of claim 18 , wherein:
the controlling the first and second gate structures impedes change in the voltage potential of the first body region in absence of an overstress event.