IC including standard cells and SRAM cells

1. An integrated circuit (IC), comprising:

a plurality of P-type gate-all-around (GAA) field-effect transistors (FETs), comprising:

at least one first P-type GAA FET comprising a plurality of silicon (Si) channel regions vertically stacked over an N-type well region; and

at least one second P-type GAA FET comprising a plurality of silicon germanium (SiGe) channel regions vertically stacked over the N-type well region;

at least one SRAM memory cell comprising the first P-type GAA FET; and

at least one standard cell or I/O cell comprising the second P-type GAA FET.

2. The IC as claimed in claim 1 , wherein each of the SiGe channel regions comprises Si-base semiconductor nanowire or nanosheet and SiGe or Ge epitaxy growth material, wherein the Si-base semiconductor nanowire or nanosheet is surrounded by the SiGe or Ge epitaxy growth material.

3. The IC as claimed in claim 2 , wherein the SiGe or Ge epitaxy growth material of each of the SiGe channel regions is surrounded by a gate electrode of the second P-type GAA FET.

4. The IC as claimed in claim 1 , wherein a first space between two adjacent Si channel regions vertically stacked and a second space between two adjacent SiGe channel regions vertically stacked are substantially the same.

5. The IC as claimed in claim 1 , wherein in the second P-type GAA FET, Ge atomic concentration in the SiGe channel regions is in a range from about 5% to about 35%.

6. The IC as claimed in claim 1 , wherein source and drain regions of the first P-type GAA FET and the second P-type GAA FET are formed by SiGe with Boron epitaxy growth material.

7. The IC as claimed in claim 1 , further comprising:

a plurality of N-type GAA FETs,

wherein each of the N-type GAA FETs comprises a plurality of Si channel regions vertically stacked over a P-type well region, and source and drain regions of the N-type GAA FETs comprise SiP, SiC, SiPC, SiAs, Si, or a combination thereof.

8. An integrated circuit (IC), comprising:

a first P-type gate-all-around (GAA) field-effect transistor (FET) comprising a plurality of first silicon (Si) channel regions vertically stacked over a substrate;

a second P-type GAA FET comprising a plurality of first silicon germanium (SiGe) channel regions vertically stacked over the substrate; and

a third P-type GAA FET comprising a plurality of second SiGe channel regions vertically stacked over the substrate,

wherein the second SiGe channel regions are surrounded by a first gate electrode,

wherein a gate dielectric layer is formed between the second SiGe channel regions and the first gate electrode, and the gate dielectric layer comprises Lanthanum-doped (La-doped) dielectric material,

wherein threshold voltages of the first, second and third P-type GAA FETs are different.

9. The IC as claimed in claim 8 , further comprising:

a fourth P-type GAA FET comprising a plurality of second Si channel regions vertically stacked over the substrate,

wherein the second Si channel regions are surrounded by a second gate electrode,

wherein a gate dielectric layer is formed between the second Si channel regions and the second gate electrode, and the gate dielectric layer comprises La-doped dielectric material.

10. The IC as claimed in claim 8 , wherein the threshold voltage of the first P-type GAA FET is greater than the threshold voltage of the third P-type GAA FET, and the threshold voltage of the third P-type GAA FET is greater than the threshold voltage of the second P-type GAA FET.

11. The IC as claimed in claim 8 , further comprising:

at least one SRAM memory cell comprising the first P-type GAA FET;

at least one first standard cell comprising the second P-type GAA FET; and

at least one second standard cell comprising the third P-type GAA FET.

12. The IC as claimed in claim 8 , further comprising:

at least one I/O cell comprising the first P-type GAA FET;

at least one first standard cell comprising the second P-type GAA FET; and

at least one second standard cell comprising the third P-type GAA FET.

13. The IC as claimed in claim 8 , wherein source and drain regions of the first, second and third P-type GAA FETs are formed by SiGe with Boron epitaxy growth material.

14. The IC as claimed in claim 8 , further comprising:

a plurality of first N-type GAA FETs,

wherein each of the first N-type GAA FETs comprises a plurality of third Si channel regions vertically stacked over the substrate, and source and drain regions of the first N-type GAA FETs comprise SiP, SiC, SiPC, SiAs, Si, or a combination thereof.

15. The IC as claimed in claim 8 , wherein the first SiGe channel regions are surrounded by a third gate electrode, wherein a gate dielectric layer is formed between the first SiGe channel regions and the third gate electrode, and the gate dielectric layer is free of La-doped dielectric material.

16. An integrated circuit (IC), comprising:

a plurality of cells arranged in an array, comprising:

a first cell, comprising at least one first P-type gate-all-around (GAA) field-effect transistor (FET) having a plurality of silicon (Si) channel regions vertically stacked over an N-type well region;

a second cell, comprising at least one second P-type GAA FET having a plurality of first silicon germanium (SiGe) channel regions vertically stacked over the N-type well region; and

a third cell, comprising at least one third P-type GAA FET having a plurality of second SiGe channel regions vertically stacked over the N-type well region,

wherein Ge atomic concentration in the first SiGe channel regions is different from Ge atomic concentration in the second SiGe channel regions.

17. The IC as claimed in claim 16 , wherein the first, second and third cells are arranged in one row of the array.

18. The IC as claimed in claim 16 , wherein Ge atomic concentration in the first SiGe channel regions is in a range from about 15% to about 35%, and Ge atomic concentration of the second SiGe channel regions is in a range from about 5% to about 14.5%.

19. The IC as claimed in claim 16 , wherein a first space between two adjacent first SiGe channel regions vertically stacked and a second space between two adjacent second SiGe channel regions vertically stacked are substantially the same.

20. The IC as claimed in claim 16 , wherein each of the first, second and third cells further comprises:

at least one N-type GAA FET,

wherein the N-type GAA FET comprises a plurality of Si channel regions vertically stacked over a P-type well region, and source and drain regions of the N-type GAA FETs comprise SiP, SiC, SiPC, SiAs, Si, or a combination thereof.