Resist filtering system having multi filters and apparatus having the resist filtering system

1. A resist coating apparatus, comprising:

a resist supplying system;

a resist filtering system having a first filter, a second filter, and a pump between the first filter and the second filter; and

a resist dispensing system,

wherein one of the first filter and the second filter includes a polar filter to remove polar foreign materials, and

wherein the resist filtering system further includes a bubble trap between the first filter and the pump.

2. The resist coating apparatus as claimed in claim 1 , wherein the polar filter includes a de-ionizing filter.

3. The resist coating apparatus as claimed in claim 1 , wherein:

the first filter includes a plurality of first unit filters connected in parallel, and

the second filter includes a plurality of second unit filters connected in parallel.

4. The resist coating apparatus as claimed in claim 3 , wherein each second unit filter of the plurality of second unit filters includes a non-polar filter to remove non-polar foreign materials.

5. The resist coating apparatus as claimed in claim 4 , wherein the second filter includes a particle removal filter.

6. The resist coating apparatus as claimed in claim 1 , further comprising:

a pre-filtering pipe connecting the resist supplying system to the resist filtering system; and

a post-filtering pipe connecting the resist filtering system to the resist dispensing system,

wherein the first filter, the pump, and the second filter are in series between the pre-filtering pipe and the post-filtering pipe.

7. The resist coating apparatus as claimed in claim 6 , wherein the resist filtering system further includes a bubble trap recycling pipe connected between the bubble trap and the pre-filtering pipe.

8. The resist coating apparatus as claimed in claim 7 , wherein:

the pre-filtering pipe includes a pre-filtering valve; and

the bubble trap recycling pipe is connected to the pre-filtering pipe ahead of the pre-filtering valve.

9. The resist coating apparatus as claimed in claim 8 , wherein the resist filtering system further includes a pump recycling pipe connected between the pump and the pre-filtering pipe.

10. The resist coating apparatus as claimed in claim 9 , wherein the pump recycling pipe is connected to the pre-filtering pipe past the pre-filtering valve.

11. The resist coating apparatus as claimed in claim 9 , wherein the pump recycling pipe includes a pump recycling valve.

12. The resist coating apparatus as claimed in claim 6 , wherein:

the resist supplying system includes a gas inlet, a resist container, a resist outlet, and a resist reserve;

the resist reserve includes a reservoir, a gas vent pipe connected to the reservoir, and a resist overflow pipe; and

the reservoir is connected to the pre-filtering pipe.

13. The resist coating apparatus as claimed in claim 12 , wherein the gas inlet includes:

a gas inlet pipe;

a gas pressure regulator to regulate a pressure of gas in the gas inlet pipe; and

a gas shut-down valve to block the gas in the gas inlet pipe.

14. The resist coating apparatus as claimed in claim 12 , wherein the reservoir includes a high level sensor, a low level sensor, and an empty sensor.

15. The resist coating apparatus as claimed in claim 12 , wherein the resist outlet includes a resist outlet pipe, a resist sensor, and a resist shut-down valve.

16. A resist coating apparatus, comprising:

a resist supplying system;

a resist filtering system including a first filter, a pump, and a second filter in series; and

a resist dispensing system,

wherein:

at least one of the first filter and the second filter include a plurality of unit filters connected in parallel, and

each unit filter of the plurality of unit filters includes a non-polar filter to remove non-polar foreign materials.

17. A resist coating apparatus, comprising:

a pre-filtering pipe;

a post-filtering pipe; and

a first filter, a pump, and a second filter in series between the pre-filtering pipe and the post-filtering pipe,

wherein:

the first filter includes a plurality of first unit filters connected in parallel,

the second filter includes a plurality of second unit filters connected in parallel,

each first unit filter of the plurality of first unit filters includes a polar filter, and

each second unit filter of the plurality of second unit filters includes a non-polar filter.