Photonic systems and methods of forming photonic systems

1. A photonic system, comprising:

a silicon-containing waveguide over a base;

an opening extending into the base;

a liner narrowing the opening;

germanium-containing detector material over the base and extending into the narrowed opening; the detector material being part of a detector configured to detect light within the waveguide; a lower region of the germanium-containing detector material within the narrowed opening having a higher concentration of defects than an upper region of the germanium-containing detector material above the narrowed opening; and

wherein the upper region extends laterally outwardly beyond the liner so that some of the upper region is directly over the liner.

2. The photonic system of claim 1 wherein the liner comprises electrically insulative material.

3. The photonic system of claim 1 wherein the liner comprises electrically conductive material.

4. A photonic system, comprising:

a silicon-containing waveguide over a monocrystalline silicon base;

an opening extending into the base;

a liner narrowing the opening;

a germanium-containing detector material over the base and extending into the narrowed opening; the detector material being part of a detector configured to detect light within the waveguide; a region of the germanium-containing detector material within the narrowed opening having a higher concentration of defects than a region of the germanium-containing detector material outside of the narrowed opening;

wherein the silicon-containing waveguide is comprised by a line spaced from the monocrystalline silicon base by one or more materials;

wherein the liner comprises a liner material; and

wherein the liner material is along sidewalls of the silicon-containing waveguide line.

5. The photonic system of claim 4 wherein the germanium-containing detector material is taller than the silicon-containing waveguide.

6. The photonic system of claim 4 wherein the germanium-containing detector material is not taller than the silicon-containing waveguide.

7. A method of forming a photonic system, comprising:

forming an opening into a monocrystalline material;

lining sidewalls of the opening with liner material, while leaving monocrystalline material exposed along a bottom of the lined opening;

epitaxially growing a detector material from the exposed monocrystalline material along the bottom of the lined opening; the detector material having a lower region within the lined opening and having an upper region over the lower region; the lower region having a higher concentration of defects than the upper region; the upper region extending laterally outward of the lower region and being across the liner material; and

forming a silicon-containing waveguide over the base and within range of a detector comprising the detector material such that the detector can be utilized to ascertain presence of light within the waveguide.

8. The method of claim 7 wherein the opening has a depth of less than or equal to about 400 nm and a maximum width of less than or equal to about 400 nm.

9. The method of claim 7 wherein the detector material is epitaxially grown germanium, and wherein the epitaxial growth of the germanium comprises:

growing the lower region while maintaining a temperature of the epitaxially growing germanium at less than or equal to about 350° C.; and

growing the upper region while maintaining a temperature of the epitaxially growing germanium at greater than or equal to about 600° C.

10. The method of claim 9 further comprising providing p-type dopant within a top region of the detector material and providing n-type dopant within a region of the base directly adjacent the detector material.

11. The method of claim 9 wherein the silicon-containing waveguide is formed after the detector material.