Semiconductor devices with dissimlar materials and methods
A semiconductor device includes a substrate comprising a first material, a first major surface, and a second major surface opposite to the first major surface, the first material having a first coefficient of thermal expansion (CTE). A filled recessed structure having recesses extends into the substrate and has a pattern in a plan view. The recesses are spaced apart so that part of the substrate is interposed between each of the recesses, and a second material different than the first material is in the recesses. The second material has a second CTE. A structure is proximate to the first major surface over the filled recessed structure and has a third CTE. The third CTE and the second CTE are different than the first CTE. The filled recessed structure reduces stresses between the substrate and structure. In some examples, the structure comprises a MIM capacitor. In other examples, the structure comprises a heterojunction semiconductor material.
1. A semiconductor device, comprising:
a substrate comprising a first material, a first major surface, and a second major surface opposite to the first major surface, the first material having a first coefficient of thermal expansion (CTE);
a filled recessed structure comprising:
recesses extending into the substrate and having a first pattern in a plan view, the recesses spaced apart so that part of the substrate is interposed between each of the recesses; and
a second material different than the first material in the recesses and having a second CTE; and
a structure at the first major surface over the filled recessed structure having a third CTE, wherein the third CTE and the second CTE are different than the first CTE;
wherein:
the second material extends out of the recesses and overlaps the first major surface.
2. The semiconductor device of claim 1 , wherein:
the third CTE and the second CTE are greater than the first CTE.
3. The semiconductor device of claim 1 , wherein:
the second CTE is greater than the first CTE and less than the third CTE.
4. The semiconductor device of claim 1 , wherein:
the structure comprises a package substrate.
5. The semiconductor device of claim 1 , wherein:
the structure comprises an insulating package material.
6. The semiconductor device of claim 1 , wherein:
the second material is a conductive material; and
the structure is a package substrate.
7. The semiconductor device of claim 1 , wherein:
the first pattern comprises a honeycomb pattern.
8. The semiconductor device of claim 1 , wherein:
the substrate comprises a power semiconductor device.
9. The semiconductor device of claim 1 , wherein:
the substrate comprises an active area: and
the filled recessed structure is at a perimeter of the substrate surrounding the active area.
10. The semiconductor device of claim 1 , wherein:
the second material is a first dielectric; and
the structure comprises:
a second dielectric over the first dielectric; and
a packaging material over the second dielectric.
11. A semiconductor device, comprising:
a substrate comprising a first material, a first major surface, and a second major surface opposite to the first major surface, the first material having a first coefficient of thermal expansion (CTE);
a filled recessed structure comprising:
a first recess filled with a second material having a second CTE, the second material contiguous with the substrate within the recess; and
a structure at the first major surface over the filled recessed structure having a third CTE, wherein:
the third CTE and the second CTE are different than the first CTE; and
the structure comprises one of a package substrate or an insulating packaging material.
12. The semiconductor device of claim 11 , wherein:
the filled recessed structure comprises recesses including the first recess extending into the substrate and having a first pattern in a plan view;
the recesses are spaced apart so that part of the substrate is interposed between each of the recesses;
the second material is in the recesses;
the second material extends out of the recesses and overlaps the first major surface; and
the second material is different than the first material.
13. The semiconductor device of claim 11 , wherein:
the substrate comprises silicon;
the semiconductor device comprises a metal-oxide-semiconductor field effect transistor (MOSFET) device;
the second material comprises a dielectric; and
the structure comprises the insulating packaging material.
14. The semiconductor device of claim 11 , wherein:
the substrate comprises silicon; and
the structure comprises the package substrate.
15. The semiconductor device of claim 11 , wherein:
the substrate has an outer perimeter at least partially surrounding an active area; and
the filled recessed structure is at the outer perimeter.
16. A method of forming a semiconductor device, comprising:
providing a substrate comprising a first material, a first major surface, and a second major surface opposite to the first major surface, the first material having a first coefficient of thermal expansion (CTE);
providing a filled recessed structure comprising:
recesses extending into the substrate and having a first pattern in a plan view, the recesses spaced apart so that part of the substrate is interposed between each of the recesses; and
a second material different than the first material in the recesses and having a second CTE; and
providing a structure at the first major surface over the filled recessed structure having a third CTE, wherein the third CTE and the second CTE are different than the first CTE;
wherein:
providing the filled recessed structure comprises providing the second material extending out of the recesses and overlapping the first major surface.
17. The method of claim 16 , wherein:
providing the substrate comprises providing the substrate comprising silicon; and
providing the structure comprises providing a package substrate.
18. The method of claim 16 , wherein:
providing the structure comprises providing a polymer based composite material.
19. The method of claim 16 , wherein:
providing the filled recessed structure comprises providing the second material as a conductor; and
providing the structure comprises providing a package substrate coupled to the second material.
20. The method of claim 16 , wherein:
providing the substrate comprises providing the substrate having an outer perimeter at least partially surrounding an active area;
providing the filled recessed structure comprises providing the filled recessed structure at the outer perimeter;
providing the substrate comprises providing the substrate comprising silicon; and
providing the structure comprises providing a metal-insulator-metal (MIM) capacitor.