Grating couplers with multiple configurations

1. A grating coupler structure, comprising:

a semiconductor substrate;

an insulator material directly contacting a top surface of the semiconductor substrate;

a polysilicon material with a first grating coupling pattern directly contacting the insulator material;

a lining material which is directly contacting and lining exposed surfaces of the polysilicon material and the insulator material;

a SiN material with a second grating coupling pattern located above the polysilicon material and the lining material;

a dielectric material directly covering the lining material over the polysilicon material and completely surrounding the SiN material; and

wiring or interconnect structures over the dielectric material,

wherein the first grating coupling pattern and the second grating coupling pattern are a same pattern.

2. The grating coupler structure of claim 1 , wherein the semiconductor substrate is below the first grating coupling pattern of the polysilicon material and the second grating coupling pattern of the SiN material.

3. The grating coupler structure of claim 2 , wherein the semiconductor substrate has a grating coupling pattern aligned with the first grating coupling pattern and the second grating coupler pattern.

4. The grating coupler structure of claim 3 , further comprising a SiN cladding layer directly over the wiring or interconnect structures.

5. The grating coupler structure of claim 2 , wherein the semiconductor substrate is a slab of non-patterned material and further comprising a cladding structure directly on the wiring or interconnect structures.

6. The grating coupler structure of claim 1 , wherein the first grating coupling pattern of the polysilicon material are polysilicon mesas.

7. The grating coupler structure of claim 1 , wherein the first grating coupling pattern of the polysilicon material is a partial etch through of the polysilicon material.

8. The grating coupler structure of claim 1 , wherein the second grating coupling pattern of the SiN material has a periodic grating pattern.

9. The grating coupler structure of claim 1 , wherein the second grating coupling pattern of the SiN material has a non-periodic grating pattern.

10. The grating coupler structure of claim 1 , wherein the first grating coupling pattern of the polysilicon material is aligned with the second grating coupling pattern of the SiN material.

11. The grating coupler structure of claim 1 , wherein the first grating coupling pattern of the polysilicon material is offset with the second grating coupling pattern of the SiN material.

12. The grating coupler structure of claim 1 , wherein the first grating coupling pattern of the polysilicon material includes one of the following shapes: square, trapezoid, inverse trapezoidal, diamond, semi-spherical, and parallelogram.

13. A grating coupler structure, comprising:

a semiconductor material;

a dielectric material directly contacting a top surface of the semiconductor material;

a polysilicon material directly contacting the dielectric material and completely embedded in additional dielectric material which is over the semiconductor material and the dielectric material, and the polysilicon material having a first grating coupler pattern;

a SiN lining material directly contacting and lining the polysilicon material and exposed surfaces of the dielectric material;

a SiN material entirely embedded in and contacting the additional dielectric material such that the SiN material is completely surrounded by and in direct contact with the additional dielectric material, and the SiN material is further located over the polysilicon material and the SiN liner, and separated from the polysilicon material by the additional dielectric material and the SiN liner such that the additional dielectric material and the SiN liner is between the SiN material and the polysilicon material, and the SiN material having a second grating coupler pattern which directs light through the first gating coupler pattern of the polysilicon material; and

wiring or interconnect structures over the additional dielectric material.

14. The grating coupler structure of claim 13 , wherein the semiconductor material includes a grating coupler pattern.

15. The grating coupler structure of claim 13 , wherein the SiN material has one of a periodic and non-periodic grating pattern.

16. The grating coupler structure of claim 15 , wherein the polysilicon material has one of a periodic and non-periodic grating pattern.

17. The grating coupler structure of claim 13 , wherein the second grating coupler pattern of the SiN material is a same pattern and aligned with the first grating coupler pattern of the polysilicon material and the SiN liner is directly contacting and over both the polysilicon material and the underlying dielectric material such that SiN liner is an intervening layer between the additional dielectric material and the polysilicon material, wherein the dielectric material, the SiN liner and the additional dielectric material are different, distinct layers.

18. The grating coupler structure of claim 13 , wherein the first grating coupling pattern of the polysilicon material includes one of the following shapes: square, trapezoid, inverse trapezoidal, diamond, semi-spherical, and parallelogram.

19. A method comprising:

forming an insulator material directly contacting a top surface of a semiconductor substrate;

forming a polysilicon material having a grating coupler pattern directly on the insulator material;

forming a liner material directly over and contacting the polysilicon material and exposed portions of the insulator material;

forming additional insulator material directly on the liner material;

forming an SiN material over the polysilicon material and the liner material, which has a grating coupler pattern which directs light through the gating coupler pattern of the polysilicon material; and

embedding the SiN material with additional dielectric material directly covering the liner material, polysilicon material and surrounding the SiN material;

forming-wiring or interconnect structures over the SiN material and the dielectric material.

20. The grating coupler structure of claim 1 , wherein the lining material is an SiN liner directly on a surface and lining the polysilicon material and the insulator material, wherein the polysilicon material is directly on the insulator material and the SiN material is surrounded by the dielectric material including between the SiN material and the SiN liner.