Circuit board

1. A circuit board comprising:

an insulating portion comprising a plurality of insulating layers,

wherein the insulating portion includes:

a first insulating portion;

a second insulating portion disposed on the first insulating portion and having a coefficient of thermal expansion corresponding to the first insulating portion; and

a third insulating portion disposed under the first insulating portion and having a coefficient of thermal expansion corresponding to the first insulating portion;

wherein the first insulating portion includes a first insulating layer including glass fibers, and

wherein the second and third insulating portions include with a second insulating layer having a coefficient of thermal expansion in the range of 10 to 65 (10 −6 m/m·k) and not including glass fibers.

2. The circuit board of claim 1 , wherein a sum of a number of layers of the second insulating layer of the second and third insulating portions satisfies a range of 10% to 30% of a total number of layers of the plurality of insulating layers.

3. The circuit board of claim 1 , wherein each of the second and third insulating portions includes:

the second insulating layer, and

a filler contained in the second insulating layer and having 40 wt % to 55 wt %.

4. The circuit board of claim 2 , wherein the sum of the number of layers of the second insulating layer of the second and third insulating portions satisfies a range of 30% to 50% of the total number of layers of the plurality of insulating layers.

5. The circuit board of claim 1 , wherein the second insulating layer each of the second and third insulating portions includes

a filler having 55 wt % to 73 wt %.

6. The circuit board of claim 1 , wherein the second insulating layer of the second and third insulating portions includes a first compound including polyphenyl ether (PPE); and a second compound including tricyclodecane and a terminal group connected to the tricyclodecane, and

wherein a weight ratio of the first compound to the second compound is 4:6 to 6:4.

7. The circuit board of claim 6 , wherein the terminal group includes at least one of an acrylate group, an epoxide group, a carboxyl group, a hydroxyl group, and an isocyanate group, and

wherein the first compound and the second compound are not chemically bound.

8. The circuit board of claim 1 , wherein the second insulating layer of the second and third insulating portions has a dielectric constant in the range of 2.03 to 2.7.

9. The circuit board of claim 1 , wherein a sum of thickness of the second insulating layer of the second and third insulating portions satisfies a range of 10% to 30% of a total thickness of the plurality of insulating layers.

10. The circuit board of claim 1 , wherein the second insulating layer of the second and third insulating portions includes a Resin Coated Copper (RCC).

11. The circuit board of claim 4 , wherein the sum of the thickness of the second insulating layer of the second and third insulating portions satisfies a range of 30% to 50% of the total thickness of the plurality of insulating layers.

12. The circuit board of claim 11 , wherein the second insulating layer includes a resin coated copper (RCC) with a coefficient of thermal expansion in the range of 10 to 50 (10−6m/m·k).

13. The circuit board of claim 1 , wherein a sum of a number of layers of the second insulating layer of the second and third insulating portions satisfies a range of 50% to 80% of a total number of layers of the plurality of insulating layers.

14. The circuit board of claim 13 , wherein a sum of thickness of the second insulating layer of the second and third insulating portions satisfies a range of 50% to 80% of a total thickness of the plurality of insulating layers.

15. The circuit board of claim 14 , wherein the second insulating layer includes a resin coated copper (RCC) with a coefficient of thermal expansion in the range of 10 to 30 (10−6m/m·k).

16. The circuit board of claim 15 , wherein the second insulating layer of each of the second and third insulating portions includes a filler having 73 wt % to 90 wt %.

17. The semiconductor package of claim 8 , wherein each of the first and second insulating layers comprises a plurality of layers,

wherein a total number of layers of the plurality of second insulating layers satisfies a range of 30% to 50% of a total number of the first and second insulating layers,

wherein a total thickness of the plurality of second insulating layers satisfies a range of 30% to 50% of a total thickness of the first and second insulating layers, and

wherein each of the second insulating layer has a coefficient of thermal expansion in a range of 10 to 50 (10−6m/m·k).

18. The semiconductor package of claim 8 , wherein each of the first and second insulating layers comprises a plurality of layers,

wherein a total number of layers of the plurality of second insulating layers satisfies a range of 50% to 80% of a total number of the first and second insulating layers,

wherein a total thickness of the plurality of second insulating layers satisfies a range of 50% to 80% of a total thickness of the first and second insulating layers, and

wherein each of the second insulating layer has a coefficient of thermal expansion in a range of 10 to 30 (10−6m/m·k).

19. A semiconductor package comprising: a first insulating layer including glass fibers; and a second insulating layer disposed on the first insulating layer and not including glass fibers; a pad disposed on the second insulating layer; and an electronic component disposed on the pad; wherein the second insulating layer has a coefficient of thermal expansion in a range of 10 to 65 (10−6m/m·k), and wherein the first insulating layer has a coefficient of thermal expansion corresponding to the coefficient of thermal expansion of the second insulating layer.

20. The semiconductor package of claim 19 , wherein each of the first and second insulating layers comprises a plurality of layers,

wherein a total number of layers of the plurality of second insulating layers satisfies a range of 10% to 30% of a total number of the first and second insulating layers, and

wherein a total thickness of the plurality of second insulating layers satisfies a range of 10% to 30% of a total thickness of the first and second insulating layers.