Semiconductor device and formation thereof
View Patent ↗A semiconductor device and method of formation are provided. The semiconductor device includes a first active region adjacent a channel, the channel, and a second active region adjacent the channel. The channel has a channel doping profile. The channel includes a central channel portion having a first dopant concentration of a first dopant and a radial channel portion surrounding the central channel portion. The radial channel portion has a second dopant concentration of a second dopant greater than the first dopant concentration. The channel comprising the central channel portion and the radial channel portion has increased voltage threshold tuning as compared to a channel that lacks a central channel portion and a radial channel portion.
1. A semiconductor device comprising:
a first source/drain region;
a channel overlying the first source/drain region, the channel having a channel doping profile and comprising:
a central channel portion having a first concentration of dopant; and
a radial channel portion surrounding the central channel portion, the radial channel portion having a second concentration of dopant greater than the first concentration of dopant; and
a second source/drain region overlying the channel, wherein the radial channel portion is disposed vertically between the central channel portion and the second source/drain region.
2. The semiconductor device of claim 1 , comprising a gate surrounding the channel.
3. The semiconductor device of claim 1 , the channel doping profile comprising at least one of a step doping profile, a linear doping profile or a Gaussian doping profile.
4. The semiconductor device of claim 1 , wherein the second source/drain region is in contact with the radial channel portion.
5. The semiconductor device of claim 1 , the first concentration of dopant between about 0.5×10 16 cm −3 to about 1.0×10 20 cm −3.
6. The semiconductor device of claim 1 , the second concentration of dopant between about 1.0×10 16 cm −3 to about 2.0×10 20 cm −3.
7. The semiconductor device of claim 1 , the central channel portion having a central channel width between about 1 nm to about 15 nm.
8. The semiconductor device of claim 1 , the radial channel portion having a radial channel width between about 3 nm to about 20 nm.
9. A semiconductor device comprising:
a first source/drain region;
a channel overlying the first source/drain region, the channel having a channel doping profile and comprising:
a central channel portion having a first concentration of dopant; and
a radial channel portion surrounding the central channel portion, the radial channel portion having a second concentration of dopant greater than the first concentration of dopant;
a second source/drain region overlying the channel; and
a gate surrounding the channel, wherein a ratio of a radial channel width of the radial channel portion divided by a central channel width of the central channel portion is between about 0.05 to about 5.
10. The semiconductor device of claim 9 , the channel doping profile comprising at least one of a step doping profile, a linear doping profile or a Gaussian doping profile.
11. The semiconductor device of claim 9 , at least one of:
the first concentration of dopant between about 0.5×10 16 cm −3 to about 1.0×10 20 cm −3 ; or
the second concentration of dopant between about 1.0×10 16 cm −3 to about 2.0×10 20 cm −3.
12. The semiconductor device of claim 9 , the central channel width between about 1 nm to about 15 nm.
13. The semiconductor device of claim 9 , the radial channel width between about 3 nm to about 20 nm.
14. A semiconductor device comprising:
a first source/drain region;
a channel overlying the first source/drain region;
a gate dielectric surrounding the channel, wherein:
a central channel portion of the channel is spaced apart from the gate dielectric by a radial channel portion of the channel,
the central channel portion has a first concentration of dopant, and
the radial channel portion has a second concentration of dopant that is greater than the first concentration of dopant; and
a second source/drain region overlying the channel, wherein the radial channel portion is disposed vertically between the central channel portion and the second source/drain region.
15. The semiconductor device of claim 14 , comprising:
a first layer in which the first source/drain region is defined; and
an insulating layer overlying the first layer, wherein the gate dielectric overlies the insulating layer.
16. The semiconductor device of claim 14 , comprising an insulating layer overlying a top surface of the gate dielectric, wherein the second source/drain region is in contact with a top surface of the insulating layer.
17. The semiconductor device of claim 14 , wherein a concentration of dopant varies linearly between a sidewall of the channel facing the gate dielectric and the central channel portion of the channel.
18. The semiconductor device of claim 14 , wherein a concentration of dopant varies according to a Gaussian distribution between a sidewall of the channel facing the gate dielectric and the central channel portion of the channel.
19. The semiconductor device of claim 14 , comprising a gate electrode overlying the gate dielectric.
20. The semiconductor device of claim 14 , comprising an insulating layer overlying a top surface of the gate dielectric.