Method of forming a photoresist layer

1. A method comprising:

providing a wafer;

spinning the wafer during a first cycle at a first speed, while a pre-wet material is dispensed over the wafer;

spinning the wafer during the first cycle at a second speed, wherein the first speed is greater than the second speed, while the pre-wet material continues to be dispensed over the wafer;

spinning the wafer during a second cycle at the first speed, while the pre-wet material continues to be dispensed over the wafer;

spinning the wafer during the second cycle at the second speed, while the pre-wet material continues to be dispensed over the wafer;

before spinning the wafer at a third speed, spinning the wafer during a third cycle at the first speed, while the pre-wet material continues to be dispensed over the wafer;

spinning the wafer during the third cycle at the second speed, while the pre-wet material continues to be dispensed over the wafer; and

spinning the wafer at the third speed, wherein the third speed is greater than the first speed, while a photoresist material is dispensed over the wafer including the pre-wet material.

2. The method of claim 1 further comprising:

after spinning the wafer at the third speed, spinning the wafer according to a predetermined speed profile to thereby control a thickness uniformity of the photoresist material across the wafer.

3. The method of claim 1 wherein the pre-wet material is a resist reducing consumption (RRC) material.

4. The method of claim 3 wherein the RRC material includes propylene glycol methyl ether acetate (PGMEA).

5. The method of claim 1 wherein the first speed is less than about 600 RPMs, and

wherein the second speed is less than about 100 RPMs.

6. The method of claim 1 wherein the first speed is maintained for a first period of time,

wherein the second speed is maintained for a second period of time, and

wherein the first period of time is greater than the second period of time.

7. A method comprising:

receiving a wafer;

accelerating the wafer to a first spin speed and dispensing a pre-wet material over the wafer while the first spin speed is maintained for a first period of time;

decelerating the wafer from the first spin speed to a second spin speed and continuing to dispense the pre-wet material over the wafer while the second spin speed is maintained for a second period of time;

accelerating the wafer from the second spin speed to a third spin speed and continuing to dispense the pre-wet material over the wafer while the third spin speed is maintained for a third period of time;

decelerating the wafer from the third spin speed to a fourth spin speed and continuing to dispense the pre-wet material over the wafer while the fourth spin speed is maintained for a fourth period of time;

accelerating the wafer to another spin speed and dispensing a photoresist material over the wafer including the pre-wet material;

before accelerating the wafer to the another spin speed, accelerating the wafer from the fourth spin speed to a fifth spin speed and continuing to dispense the pre-wet material over the wafer while the fifth spin speed is maintained for a fifth period of time; and

decelerating the wafer from the fifth spin speed to a sixth spin speed and continuing to dispense the pre-wet material over the wafer while the sixth spin speed is maintained for a sixth period of time.

8. The method of claim 7 further comprising:

before dispensing the photoresist material over the wafer including the pre-wet material, dispensing a bottom antireflective coating (BARC) material over the wafer including the pre-wet material.

9. The method of claim 7 further comprising:

stopping the dispensing of the photoresist material; and

after stopping the dispensing of the photoresist material, accelerating and decelerating the wafer according to a predetermined speed profile to thereby control a thickness uniformity of the photoresist material across the wafer.

10. The method of claim 7 wherein the first, third, and fifth spin speeds are substantially the same,

wherein the second, fourth, and sixth spin speeds are substantially the same,

wherein the first, third, and fifth periods of time are substantially the same, and

wherein the second, fourth, and sixth periods of time are substantially the same.

11. The method of claim 7 wherein the first, third, and fifth spin speeds are different,

wherein the second, fourth, and sixth spin speeds are different,

wherein the first, third, and fifth periods of time are different, and

wherein the second, fourth, and sixth periods of time are different.

12. The method of claim 10 wherein the first spin speed ranges from about 300 RPMs to about 600 RPMs, and

wherein the second spin speed ranges from about 0 RPMs to about 20 RPMs.

13. The method of claim 10 wherein the first period of time is less than about 2 seconds, and

wherein the second period of time is less than about 1 second.

14. A method comprising:

receiving a wafer in a wafer processing device;

coating the wafer with a pre-wet material while a multi-loop process is performed on the wafer in the wafer processing device, wherein the multi-loop process includes:

accelerating the wafer to a first spin speed and maintaining the first spin speed for a first period of time;

decelerating the wafer from the first spin speed to a second spin speed and maintaining the second spin speed for a second period of time;

accelerating the wafer from the second spin speed to a third spin speed and maintaining the third spin speed for a third period of time;

decelerating the wafer from the third spin speed to a fourth spin speed and maintaining the fourth spin speed for a fourth period of time;

accelerating the wafer from the fourth spin speed to a fifth spin speed and maintaining the fifth spin speed for a fifth period of time; and

decelerating the wafer from the fifth spin speed to a sixth spin speed and maintaining the sixth spin speed for a sixth period of time; and

after the multi-loop process, accelerating the wafer to another spin speed and dispensing a photoresist material over the wafer including the pre-wet material.

15. The method of claim 14 further comprising:

performing a modulation process on the wafer according to a predetermined speed profile to thereby control a thickness uniformity of the photoresist material across the wafer.

16. The method of claim 15 further comprising:

before coating the wafer including the pre-wet material with a photoresist material, coating the wafer including the pre-wet material with a bottom antireflective coating (BARC) material.