MOS TRANSISTOR ON SOI STRUCTURE
A device includes an active semiconductor layer on top of and in contact with an insulating layer which overlies a semiconductor substrate. A transistor for the device includes a source region, a drain region, and a body region arranged in the active semiconductor layer. The body region of the transistor is electrically coupled to the semiconductor substrate using a conductive via that crosses through the insulating layer.
1 . A device, comprising:
a semiconductor substrate;
an insulating layer on top of and in contact with the semiconductor substrate;
an active semiconductor layer on top of and in contact with the insulating layer;
a transistor comprising a source region, a drain region, and a body region arranged in the active semiconductor layer; and
a conductive via configured to electrically connect the body region to the semiconductor substrate;
wherein said conductive via crosses through the insulating layer.
2 . The device according to claim 1 , further comprising a body contact pad connected to the body region, wherein the body contact pad is connected to the conductive via by a metal track of an interconnection network of the device.
3 . The device according to claim 2 , wherein said metal track is entirely arranged in a lowest metal track level of the interconnection network.
4 . The device according to claim 1 , wherein the conductive via is laterally insulated from the active layer.
5 . The device according to claim 4 , further comprising a shallow trench isolation surrounding the transistor, and wherein the conductive via passes through the shallow trench isolation.
6 . The device according to claim 1 , wherein the conductive via is made of a metallic material.
7 . The device according to claim 6 , wherein the metallic material is tungsten.
8 . The device according to claim 1 , wherein the transistor comprises a stack of a gate insulator and a conductive gate topping the body region between the source and drain regions.
9 . The device according to claim 1 , wherein the active semiconductor layer is partially depleted.
10 . A device, comprising:
a semiconductor substrate;
an insulating layer on top of and in contact with the semiconductor substrate;
an active semiconductor layer on top of and in contact with the insulating layer;
a plurality of transistors, wherein each transistor comprises a source region, a drain region, and a body region arranged in the active semiconductor layer; and
a conductive via configured to electrically connect the body region of at least one of the plurality of transistors to the semiconductor substrate;
wherein said conductive via crosses through the insulating layer.
11 . The device according to claim 10 , wherein said conductive via is provided for connecting the body region of each of the plurality of transistors to the semiconductor substrate.
12 . The device according to claim 10 , wherein said conductive via is electrically connected to the body regions of multiple ones of said plurality of transistors.
13 . The device according to claim 10 , wherein the conductive via is laterally insulated from the active layer.
14 . The device according to claim 13 , further comprising a shallow trench isolation surrounding one or more of the plurality of transistors, and wherein the conductive via passes through the shallow trench isolation.
15 . The device according to claim 10 , wherein the active semiconductor layer is partially depleted.
16 . A method of manufacturing a device in a semiconductor on insulator substrate including a semiconductor substrate, an insulating layer on top of and in contact with the semiconductor substrate, and an active semiconductor layer on top of and in contact with the insulating layer, the method comprising:
forming a transistor supported by said semiconductor on insulator substrate, wherein the transistor includes a source region, a drain region, and a body region in the active semiconductor layer; and
forming a conductive via to electrically connect the body region of the transistor to the semiconductor substrate;
wherein forming the conductive via comprises passing the conductive via to cross through the insulating layer of the semiconductor on insulator substrate.
17 . The method according to claim 16 , wherein the transistor further includes a body contact pad that is connected to the body region, and further comprising connecting the body contact pad to the conductive via by a metal track of an interconnection network.
18 . The method according to claim 17 , wherein the body contact pad and the conductive via are simultaneously formed during a same metal deposition step.
19 . The method according to claim 16 , further comprising:
forming a shallow trench isolation surrounding the transistor; and
wherein forming the conductive via comprises extending the conductive via through the shallow trench isolation.