We claim: 1. A nanosheet Metal Oxide Semiconductor (MOS) device (100), comprising:
a first region (104) of a first conductivity type and a second region (106) of a second conductivity type formed on a substrate (102), wherein the first region (104) is adjacent to the second region (106);
a drain fin (108) and a source fin (110) of the first conductivity type extending from a top surface of the first region (104) and the second region (106), respectively;
a gate stack (112) formed between the drain fin (108) and the source fin (110), the gate stack (112) comprising:
a channel region (114) comprising a first set of vertically stacked nanosheets of the second conductivity type, wherein one end of each nanosheet of the first set of vertically stacked nanosheets is connected to the source fin (110) and other end of each nanosheet of the first set of vertically stacked nanosheets extend perpendicularly from a first lateral surface (111a) of the source fin (110), and
a gate metal (116) wrapping around the channel region (114) on all sides; and an extension region (118) comprising:
an extension fin (120) of the first conductivity type placed between the gate stack (112) and the drain fin (108), extending perpendicularly from a top surface of the first region (104),
wherein the extension fin (120) comprises a first lateral surface (121a) and a second lateral surface (121b),
wherein the first lateral surface (121a) of the extension fin (120) is in contact with the channel region (114); and
a second set of vertically stacked nanosheets (122) of the first conductivity type extending perpendicularly from the second lateral surface (121b) of the extension fin (120) to contact the drain fin (108).

2. The nanosheet MOS device (100) as claimed in claim 1, comprises an anode fin (124)
of the second conductivity type that extends perpendicularly from the top surface of the
first region (104); and
wherein the anode fin (124) is doped with a second material type.
3. The nanosheet MOS device (100) as claimed in claim 1, comprises a body fin (126) extending perpendicularly from the top surface of the second region (106), wherein the body fin (126) is doped with a second material type.
4. The nanosheet MOS device (100) as claimed in claim 1, wherein the drain fin (108), the source fin (110), the extension fin (120) and the body fin (126) are non-silicided.
5. The nanosheet MOS device (100) as claimed in claim 1, wherein at least a part of: the drain fin (108), the source fin (110), and the body fin (126) are silicided with a silicide layer.
6. The nanosheet MOS device (100) as claimed in claim 1, wherein the first region (104) is doped with a first material type and the second region (106) is doped with a second material type.
7. The nanosheet MOS device (100) as claimed in claim 1, wherein the extension fin (120) is doped with a first material type.
8. The nanosheet MOS device (100) as claimed in claim 1, wherein the drain fin (108) and the source fin (110) of the first conductivity type are doped with a first material type.
9. The nanosheet MOS device (100) as claimed in claim 1, wherein the gate metal (116) is formed using Titanium Nitride (TiN), and
wherein a combination of silicon dioxide (SiO2) and Hafnium oxide (HfO2) are used as gate oxide.

10. The nanosheet MOS device (100) as claimed in claim 1, wherein a length of the first set of vertically stacked nanosheets and a length of the second set of vertically stacked nanosheets (122) are different.
11. The nanosheet MOS device (100) as claimed in claim 1, wherein a thickness of one or more vertically stacked nanosheets of the first set of vertically stacked nanosheets is lesser than a thickness of one or more vertically stacked nanosheets of the second set of vertically stacked nanosheets (122).
12. A nanosheet Metal Oxide Semiconductor (MOS) device (200), comprising:
a first region (104) of a first conductivity type and a second region (106) of a second conductivity type formed on a substrate (102), wherein the first region (104) is adjacent to the second region (106);
one or more drain fins (202a, 202b) and a source fin (110) of the first conductivity type extending from a top surface of the first region (104) and the second region (106), respectively;
an anode fin (124) of the second conductivity type extending perpendicularly from the top surface of the first region (104);
a body fin (126) of the second conductivity type extending from the top surface of the second region (106);
a gate stack (112) formed between the one or more drain fins (202a, 202b) and the source fin (110), the gate stack (112) comprising:
a channel region (114) comprising a first set of vertically stacked nanosheets of the second conductivity type, wherein one end of each nanosheet of the first set of vertically stacked nanosheets are connected to the source fin (110) and other end of each nanosheet of the first set of vertically stacked nanosheets extend perpendicularly from a first lateral surface (111a) of the first source fin, and
a gate metal (116) wrapping around the channel region (114) on all sides; and

an extension region (118) comprising:
an extension fin (120) of the first conductivity type placed between the gate stack (112) and the one or more drain fins, extending perpendicularly from a top surface of the first region (104),
wherein the extension fin (120) comprises a first lateral surface (121a) and a second lateral surface (121b),
wherein the first lateral surface (121a) of the extension fin (120) is in contact with the channel region (114);
a second set of vertically stacked nanosheets (122) of the first conductivity type extending perpendicularly from the second lateral surface (121b) of the extension fin (120) to contact a first drain fin (202b) of the one or more drain fins (202a, 202b); and
wherein the first region (104) includes a first transistor (128) of a first type and the second region (106) includes a second transistor (130) of a second type to embed a silicon-controlled rectifier (SCR) within the nanosheet MOS device (100).
13. The nanosheet MOS device (200) as claimed in claim 12, wherein a first emitter of the
first transistor (128) is connected to the anode fin (124), a second emitter of the second
transistor (130) is connected to the source fin (110), a first base of the first transistor
(128) is connected to a second collector of the second transistor (130), a first collector
of the first transistor (128) is connected to a second base of the second transistor (130),
and
wherein the second base is connected to the body fin (126) and the first base is connected to the one or more drain fins (202a, 202b).
14. The nanosheet MOS device (200) as claimed in claim 12, wherein the anode fin (124), the one or more drain fins (202a, 202b), the source fin (110), the extension fin (120) and the body fin (126) are non-silicided.
15. The nanosheet MOS device (200) as claimed in claim 12, wherein at least a part of: the anode fin (124), the one or more drain fins (202a, 202b), the source fin (110), and the body fin (126) are silicided with a silicide layer.

16. The nanosheet MOS device (200) as claimed in claim 12, wherein the first region (104) is doped with a first material type and the second region (106) is doped with a second material type.
17. The nanosheet MOS device (200) as claimed in claim 12, wherein a number of the drain fins (202a, 202b) are greater than a number of anode fin (124).
18. The nanosheet MOS device (200) as claimed in claim 12, wherein the extension fin (120) is moderately doped with a first material type.
19. The nanosheet MOS device (200) as claimed in claim 12, wherein the one or more drain fins (202a, 202b) and the source fin (110) of the first conductivity type are doped with a first material type.
20. The nanosheet MOS device (200) as claimed in claim 12, wherein the gate metal (116) is formed using Titanium Nitride (TiN), and
wherein a combination of silicon dioxide (SiO2) and Hafnium oxide (HfO2) are used as gate oxide.
21. The nanosheet MOS device (200) as claimed in claim 12, wherein a length of the first set of vertically stacked nanosheets and a length of the second set of vertically stacked nanosheets (122) are different.
22. The nanosheet MOS device (200) as claimed in claim 12, wherein a thickness of one or more vertically stacked nanosheets of the first set of vertically stacked nanosheets is lesser than a thickness of one or more vertically stacked nanosheets of the second set of vertically stacked nanosheets (122).
Dated this 6th day of February 2023