Package structure

1 . A package structure, comprising:

a first substrate;

a second substrate disposed under the first substrate;

a gap between the first substrate and the second substrate, wherein the gap comprises a first region and a second region, the first region is configured to accommodate a filling material; and

a directing structure disposed in a flow path of the filling material and configured to reduce a migration of the filling material from the first region to the second region,

wherein the second substrate comprises an upper surface facing the first substrate and a trench recessed from the upper surface of the second substrate, wherein the directing structure is disposed in the trench,

wherein the directing structure comprises a plurality of protrusions arranged in an array, and wherein the plurality of protrusions is staggered from a top view.

2 . The package structure of claim 1 , wherein the trench is configured to accommodate the filing material.

3 . The package structure of claim 2 , wherein the plurality of protrusions protrudes from an inner surface of the trench.

4 . The package structure of claim 1 , wherein the trench has a lateral surface and the plurality of protrusions extends in a direction non-parallel to the lateral surface of the trench from the top view.

5 . The package structure of claim 1 , wherein the plurality of protrusions comprises a first protrusion having a first width and a second protrusion having a second width different from the first width.

6 . The package structure of claim 1 , wherein the plurality of protrusions comprises a first protrusion having a first length and a second protrusion having a second length different from the first length.

7 . The package structure of claim 1 , wherein the plurality of protrusions extends in a direction non-parallel to the flow path from the top view.

8 . A package structure, comprising:

a substrate;

a carrier disposed under the substrate and having a first upper surface facing the substrate;

a filling material disposed between the substrate and the first upper surface of the carrier, and

an adhesion enhancement structure disposed on the first upper surface of the carrier and configured to reduce an extent of delamination between the filling material and the first upper surface of the carrier,

wherein the adhesion enhancement structure comprises a plurality of protrusions having a cross-section tapering toward the substrate.

9 . The package structure of claim 8 , wherein the plurality of protrusions comprises a first protrusion and a second protrusion extending in different directions from each other from a top view.

10 . The package structure of claim 8 , wherein the plurality of protrusions comprises a first protrusion having a first height and a second protrusion having a second height different from the first height.

11 . The package structure of claim 8 , wherein the carrier comprises a trench recessed from the first upper surface and located under the substrate, and wherein the trench has an inner lateral surface extending non-parallel to a lateral surface of the protrusions.

12 . A package structure, comprising:

a substrate comprising a first portion having a first value of flexural modulus and a second portion having a second value of flexural modulus smaller than the first value of flexural modulus;

a carrier disposed under the substrate;

a gap between the substrate and the carrier; and

a directing structure disposed in the gap, wherein the directing structure is located between the first portion and the second portion of the substrate from a top view.

13 . The package structure of claim 12 , wherein the directing structure comprises a plurality of protrusions extending from the carrier toward the substrate.

14 . The package structure of claim 13 , further comprising a groove recessed from an upper surface of the carrier facing the substrate, wherein the protrusions are disposed in the groove.

15 . The package structure of claim 12 , further comprising a filling material in the gap, wherein the filling material is in contact with the first portion of the substrate and free from being in contact with the second portion of the substrate.

16 . The package structure of claim 14 , wherein the gap comprises a first region under the first portion of the substrate and a second region under the second portion of the substrate, and wherein the first region of the gap has a height greater than a second height of the second region of the gap.