Apparatus for ESD protection
A structure comprises an N+ region formed over a substrate, a P+ region formed over the substrate, wherein the P+ region and the N+ region form a diode and a first epitaxial growth block region formed between the N+ region and the P+ region.
1. A structure comprising:
an N+ region formed over a substrate;
a P+ region formed over the substrate, wherein the P+ region and the N+ region form a diode; and
a first epitaxial growth block region formed between the N+ region and the P+ region, wherein the first epitaxial growth block region comprises silicon nitride.
2. The structure of claim 1 , wherein:
the N+ region is formed in an n-well of the substrate; and
the P+ region is formed in the n-well of the substrate, and wherein the N+ region and the P+ region form a p-type electrostatic discharge (ESD) protection diode.
3. The structure of claim 1 , wherein:
the N+ region is formed in a p-well of the substrate; and
the P+ region is formed in the p-well of the substrate, and wherein the N+ region and the P+ region form an n-type ESD protection diode.
4. The structure of claim 1 , further comprising:
a second epitaxial growth block region formed on an opposite side of the N+ region with respect to the first epitaxial growth block region; and
a third epitaxial growth block region formed on an opposite side of the P+ region with respect to the first epitaxial growth block region.
5. The structure of claim 4 , wherein:
the second epitaxial growth block region comprises silicon nitride; and
the third epitaxial growth block region comprises silicon nitride.
6. The structure of claim 1 , wherein:
the first epitaxial growth block region is of a width approximately equal to 144 nm.
7. A system comprising:
an integrated circuit comprising:
a first terminal coupled to a first voltage rail;
a second terminal coupled to an input/output pad; and
a third terminal coupled to a second voltage rail;
a first electrostatic discharge (ESD) protection diode coupled between the first voltage rail and the input/output pad, wherein the first ESD protection diode comprises:
a first N+ region formed in an n-well of a substrate;
a first P+ region formed in the n-well of the substrate; and
a first epitaxial growth block region formed between the first N+ region and the first P+ region; and
a second ESD protection diode coupled between the second voltage rail and the input/output pad, wherein the second ESD protection diode comprises:
a second N+ region formed in a p-well of the substrate;
a second P+ region formed in the p-well of the substrate; and
a second epitaxial growth block region formed between the second N+ region and the second P+ region.
8. The system of claim 7 , wherein:
the first epitaxial growth block region comprises silicon nitride; and
the second epitaxial growth block region comprises silicon nitride.
9. The system of claim 7 , wherein:
the first voltage rail is connected to a power source; and
the second voltage rail is connected to ground.
10. The system of claim 7 , wherein:
the first N+ region is coupled to the first voltage rail;
the first P+ region is coupled to the input/output pad;
the second N+ region is coupled to the input/output pad; and
the second P+ region is coupled to the second voltage rail.
11. The system of claim 7 , further comprising:
a plurality of p-type ESD protection diodes connected in parallel with the first ESD protection diode; and
a plurality of n-type ESD protection diodes connected in parallel with the second ESD protection diode.
12. The system of claim 11 , wherein:
each active region of the plurality of p-type ESD protection diodes is separated from an adjacent active region by an epitaxial growth block region; and
each active region of the plurality of n-type ESD protection diodes is separated from an adjacent active region by the epitaxial growth block region.
13. The system of claim 7 , wherein:
the first ESD protection diode is a p-type ESD protection diode having an anode coupled to the input/output pad and a cathode coupled to the first voltage rail.
14. The system of claim 7 , wherein:
the second ESD protection diode is an n-type ESD protection diode having an anode coupled to the second voltage rail and a cathode coupled to the input/output pad.
15. A method comprising:
forming an active region including a plurality of fins;
depositing an epitaxial growth block layer over the active region;
patterning the epitaxial growth block layer to define a first growth area for an N+ region and a second growth area for a P+ region;
removing portions of the active region in the first growth area and the second growth area; and
growing the N+ region and the P+ region through an epitaxial growth process, wherein the N+ region and the P+ region form an electrostatic discharge (ESD) protection diode.
16. The method of claim 15 , wherein:
the N+ region is formed in a p-well of a substrate; and
the P+ region is formed in the p-well of the substrate, and wherein the N+ region and the P+ region form an n-type ESD protection diode.
17. The method of claim 15 , wherein:
the N+ region is formed in an n-well of a substrate; and
the P+ region is formed in the n-well of the substrate, and wherein the N+ region and the P+ region form a p-type ESD protection diode.
18. The method of claim 15 , further comprising:
forming a first contact on the N+ region, wherein the first contact is a cathode of the ESD protection diode; and
forming a second contact on the P+ region, wherein the second contact is an anode of the ESD protection diode.
19. The method of claim 15 , wherein:
the epitaxial growth block layer comprises silicon nitride.