Ferroelectric field-effect transistors with a hybrid well
Structures including a ferroelectric field-effect transistor and methods of forming a structure including a ferroelectric field-effect transistor. The structure comprises a semiconductor substrate, a semiconductor layer, a dielectric layer arranged between the semiconductor layer and the semiconductor substrate, and first and second wells in the semiconductor substrate. The first well has a first conductivity type, and the second well has a second conductivity type opposite to the first conductivity type. A ferroelectric field-effect transistor comprises a gate structure on the semiconductor layer over the first well and the second well. The gate structure includes a ferroelectric layer comprising a ferroelectric material.
1. A structure comprising:
a semiconductor substrate;
a semiconductor layer;
a dielectric layer arranged between the semiconductor layer and the semiconductor substrate;
a first well in the semiconductor substrate, the first well having a first conductivity type;
a second well in the semiconductor substrate, the second well having a second conductivity type opposite to the first conductivity type; and
a ferroelectric field-effect transistor comprising a gate structure on the semiconductor layer over the first well and the second well, the gate structure including a ferroelectric layer comprising a ferroelectric material.
2. The structure of claim 1 wherein the first well and the second well adjoin along a p-n junction, and the ferroelectric layer is positioned to overlap with the p-n junction.
3. The structure of claim 2 wherein the ferroelectric layer includes a first portion that overlaps with the first well and a second portion that overlaps with the second well.
4. The structure of claim 3 wherein the first portion of the ferroelectric layer adjoins the second portion of the ferroelectric layer.
5. The structure of claim 1 further comprising:
a first power supply coupled to the first well, the first power supply configured to supply a positive bias voltage to the first well.
6. The structure of claim 5 further comprising:
a second power supply coupled to the second well, the first power supply configured to supply a negative bias voltage to the second well.
7. The structure of claim 6 wherein the positive bias voltage is greater than 0 volts and less than or equal to 4 volts, and the negative bias voltage is less than 0 volts and greater than or equal to negative 4 volts.
8. The structure of claim 1 wherein the first well is configured to receive a positive bias voltage.
9. The structure of claim 8 wherein the second well is configured to receive a negative bias voltage.
10. The structure of claim 9 wherein the positive bias voltage is greater than 0 volts and less than or equal to 4 volts, and the negative bias voltage is less than 0 volts and greater than or equal to negative 4 volts.
11. The structure of claim 1 wherein the ferroelectric layer is a singular layer.
12. The structure of claim 1 wherein the ferroelectric material is hafnium oxide or zirconium oxide.
13. The structure of claim 1 wherein the dielectric layer is a buried oxide layer of a silicon-on-insulator substrate.
14. The structure of claim 1 wherein the ferroelectric field-effect transistor comprises a first source/drain and a second source/drain, the ferroelectric layer includes a first portion adjacent to the first source/drain, the first portion of the ferroelectric layer overlaps with the first well, the ferroelectric layer includes a second portion adjacent to the second source/drain, and the second portion of the ferroelectric layer overlaps with the second well.
15. The structure of claim 14 wherein the first well and the second well adjoin along a p-n junction, the ferroelectric layer is positioned to overlap with the p-n junction, and the p-n junction is positioned in a lateral direction between the first source/drain and the second source/drain.
16. The structure of claim 14 wherein the first portion of the ferroelectric layer adjoins the second portion of the ferroelectric layer.
17. The structure of claim 1 further comprising:
a first well contact connected to the first well, the first well contact having the first conductivity type; and
a second well contact connected to the second well, the second well contact having the second conductivity type.
18. The structure of claim 17 wherein the first well and the second well adjoin along a p-n junction, and p-n junction is positioned in a lateral direction between the first well contact and the second well contact.
19. The structure of claim 17 wherein the first well and the second well adjoin along a p-n junction, the ferroelectric layer includes a first portion positioned over a portion of the first well, the ferroelectric layer includes a second portion positioned over a portion of the second well, and the first portion and the second portion are symmetrically arranged about the p-n junction.
20. A method comprising:
forming a first well and a second well in a semiconductor substrate, wherein the first well has a first conductivity type, and the second well has a second conductivity type opposite to the first conductivity type; and
forming a ferroelectric field-effect transistor comprising a gate structure on a semiconductor layer over the first well and the second well, wherein a dielectric layer is arranged between the semiconductor layer and the semiconductor substrate, and the gate structure includes a ferroelectric layer comprising a ferroelectric material.