Backlight assembly, display module having the backlight assembly and method of manufacturing the backlight assembly

1. A backlight assembly comprising:

a light source unit generating light;

a mold frame receiving the light source unit; and

a bottom chassis including:

a bottom plate;

first, second, third and fourth sidewalls extending from the bottom plate;

an extension part bent from at least one of the sidewalls, wherein the extension part overlaps an adjacent sidewall;

a first hole formed at the extension part; and

a second hole corresponding to the first hole, wherein the second hole is formed at the adjacent sidewall overlapping the extension part, the first hole overlapping the second hole,

wherein a combination part is formed at a side of the mold frame, and the combination part penetrates the overlapped first and the second holes.

2. The backlight assembly of claim 1 , wherein the mold frame and the bottom chassis are integrally formed.

3. The backlight assembly of claim 1 , wherein the extension part overlaps the adjacent sidewall at a corner of the bottom chassis.

4. The backlight assembly of claim 1 , wherein the first and the second holes are formed in a circular shape, and a cross-section of the combination part is formed in a circular shape.

5. The backlight assembly of claim 4 , wherein a cross-section of an end portion of the combination part is slightly larger than cross-sections of the first and the second holes.

6. The backlight assembly of claim 1 , wherein the first and the second holes are formed in a rectangular shape, and

a cross-section of the combination part is formed in a rectangular shape.

7. The backlight assembly of claim 1 , wherein the extension part overlaps an adjacent extension part at a corner of the mold frame, and is combined with the adjacent extension part at an overlapping part of the extension part and the adjacent extension part.

8. The backlight assembly of claim 7 , wherein a hole is formed at the overlapping part of the extension part and the adjacent extension part.

9. The backlight assembly of claim 8 , wherein a combination part is formed at a side of the mold frame, and the combination part penetrates the hole.

10. The backlight assembly of claim 9 , wherein the hole is formed in a rectangular shape having a center at the corner of the bottom chassis, and a cross-section of the combination part is formed in a rectangular shape.

11. The backlight assembly of claim 10 , wherein the extension part comprises a curved face at the corner of the bottom chassis.

12. The backlight assembly of claim 1 , wherein the sidewall comprises a hemming structure.

13. A display module comprising:

a display panel;

a light source unit providing light to the display panel;

a mold frame receiving the backlight unit; and

a bottom chassis including:

a bottom plate;

first, second, third and fourth sidewalls extending from the bottom plate;

an extension part bent from at least one of the first, second, third and fourth sidewalls, wherein the extension part overlaps an adjacent sidewall;

a first hole formed at the extension part; and

a second hole corresponding to the first hole, wherein the second hole is formed at the adjacent sidewall overlapping the extension part, the first hole overlapping the second hole,

wherein a combination part is formed at a side of the mold frame, and the combination part penetrates the overlapped first and the second holes.

14. The display module of claim 13 , wherein the mold frame and the bottom chassis are integrally formed.

15. The display module of claim 13 , wherein the extension part overlaps the adjacent sidewall at a corner of the bottom chassis.

16. The display module of claim 13 , wherein the second and fourth sidewalls respectively comprise extension parts extended to the first and third sidewalls, the first and third sidewalls respectively overlap the extension parts of the second and fourth sidewalls, and holes are respectively formed at areas of the first and third sidewalls overlapping the extension parts of the second and fourth sidewalls.

17. The display module of claim 13 , wherein the extension parts respectively overlap the adjacent extension parts, and

holes are respectively formed at areas of the extension parts overlapping the adjacent extension parts.

18. The display module of claim 17 , wherein combination parts are disposed at sides of the mold frame, and the combination parts respectively penetrate the holes of the extension parts of the first, second, third and fourth sidewalls.

19. The display module of claim 13 , wherein the sidewall comprises a hemming structure.

20. A method of manufacturing a backlight assembly, the method comprising:

forming a bottom chassis, the bottom chassis including a bottom plate, first, second, third and fourth sidewalls extending from the bottom plate, and an extension part bent from at least one of the first, second, third and fourth sidewalls and overlapping an adjacent sidewall;

forming a first hole at an end portion of the extension part and a second hole at an end portion of the sidewall;

folding the extension part to overlap the first hole of the sidewall with the second hole of the adjacent sidewall;

combining the bottom chassis with a mold frame; and

disposing a light source unit in the mold frame,

wherein combining the bottom chassis with a mold frame includes inserting a combination part formed at a side of the mold frame into the overlapped first and the second holes.

21. The method of claim 20 , wherein extension parts are respectively formed to be extended from the first and third sidewalls, the extension parts are extended to the adjacent sidewall, and the extension parts respectively overlap the second and fourth sidewalls.

22. The method of claim 20 , wherein forming the bottom chassis further comprises bending at least one extended portion of the first, second, third and fourth sidewalls in a perpendicular direction to the bottom plate.