Integrating a junction field effect transistor into a vertical field effect transistor
Embodiments of the invention include first and second devices formed on a substrate. The first device includes a bottom source or drain (S/D) region, a plurality of fins formed on portions of the bottom S/D region, a bottom spacer formed on the bottom S/D region, a dielectric layer, a gate, a top S/D region formed on each fin of a plurality of fins, and one or more contacts. The dielectric layer is disposed between the gate and the fin of the plurality of fins. The second device includes a bottom doped region, a channel formed the bottom doped region, a sidewall doped region of the channel, a gate coupled to the sidewall doped region, a top doped region, and one or more contacts. A junction is formed between the channel and the sidewall doped region. The cap layer is formed on the gate and the top doped region.
1. A set of semiconductor devices formed on a substrate, the set of semiconductor devices comprising:
a first semiconductor device formed on a substrate, wherein the first semiconductor device comprises:
a bottom source and drain (S/D) region;
a plurality of fins formed on one or more portions of the bottom S/D region;
a bottom spacer layer formed on the bottom S/D region;
a dielectric layer;
a gate, wherein the dielectric layer is disposed between the gate and a fin of the plurality of fins;
a cap layer formed on the bottom spacer layer and the gate;
a top S/D region formed on each fin of the plurality of fins; and
one or more contacts; and
a second semiconductor device formed on the substrate, wherein the second semiconductor device comprises:
a bottom doped region;
a channel formed on a portion of the bottom doped region;
a sidewall doped region of the channel, wherein a junction is formed between the channel and the sidewall doped region;
a gate coupled to the sidewall doped region;
a top doped region, wherein the cap layer is formed on the gate and the top doped region; and
one or more contacts.
2. The devices of claim 1 , wherein the first semiconductor device comprises a vertical fin field effect transistor and the second semiconductor device comprises a junction field effect transistor.
3. The devices of claim 1 , wherein the junction is formed between the channel and the sidewall doped region, wherein the sidewall doped region is a wrap-around region.
4. The devices of claim 1 , wherein the channel of the junction field effect transistor pinches off vertically.
5. The devices of claim 1 , wherein the channel width dimension is greater than a fin width dimension of the plurality of fins.
6. The devices of claim 1 , wherein a contact of the one or more contacts for the junction field effect transistor comprises an extended contact.
7. The devices of claim 6 , wherein the extended contact enables a larger voltage.
8. The devices of claim 1 , wherein the gate of the first semiconductor device and the second semiconductor device are simultaneously formed gates.
9. The devices of claim 1 , wherein the gate of the first semiconductor device comprises a wrap-around gate.
10. The devices of claim 1 , wherein the gate of the second semiconductor device comprises a wrap-around gate.
11. The devices of claim 1 further comprising a shallow trench isolation region between the first semiconductor device and the second semiconductor device.
12. The devices of claim 1 , wherein the channel comprises sidewalls and a main body region.
13. The devices of claim 12 , wherein the sidewalls of the channel comprise a different type of material than the main body region of the channel.
14. The devices of claim 13 , wherein the sidewalls are doped regions that are in-situ doped regions.
15. The devices of claim 14 , wherein a dopant concentration of the doped regions of the sidewalls range from 1×10 19 cm −3 to 2×10 21 cm −3 .
16. The devices of claim 14 , wherein the bottom doped regions are only below the second semiconductor device.
17. The devices of claim 1 , wherein the dielectric layer comprises a high-k dielectric layer.
18. The devices of claim 1 , wherein there is no high-k dielectric layer on the gate of the second semiconductor device.
19. The devices of claim 1 , wherein the one or more contacts of the first semiconductor device and the one or more contacts of the second semiconductor device comprise of tungsten.
20. The devices of claim 19 , wherein the one or more contacts of the first semiconductor device and the one or more contacts of the second semiconductor device comprises a metal lines, wherein the metal liner is a Ti/TiN liner.