Method for cleaning a semiconductor wafer composed of silicon directly after a process of polishing of the semiconductor wafer
View Patent ↗A method for cleaning a semiconductor wafer composed of silicon directly after a process of chemical mechanical polishing of the semiconductor wafer includes transferring the semiconductor wafer from a polishing plate to a first cleaning module and spraying both side surfaces of the semiconductor wafer with water at a pressure no greater than 1000 Pa at least once while transferring the semiconductor wafer. The semiconductor wafer is then cleaned between rotating rollers with water. The side surfaces of the semiconductor wafer are sprayed with an aqueous solution containing hydrogen fluoride and a surfactant at a pressure no greater than 70,000 Pa. Subsequently, the side surfaces are sprayed with water at a pressure no greater than 20,000 Pa. The wafer is then dipped into an aqueous alkaline cleaning solution, and then cleaned between rotating rollers with a supply of water. The semiconductor wafer is then sprayed with water and dried.
1. A method for cleaning a semiconductor wafer composed of silicon directly after a process of chemical mechanical polishing of the semiconductor wafer, the method comprising the following steps in the order indicated:
a) transferring the semiconductor wafer from a polishing plate to a first cleaning module, and spraying both side surfaces of the semiconductor wafer with water at a pressure no greater than 1000 Pa at least once while transferring the semiconductor wafer;
b) cleaning the semiconductor wafer between rotating rollers with a supply of water;
c) spraying the side surfaces of the semiconductor wafer with an aqueous solution containing hydrogen fluoride and a surfactant at a pressure no greater than 70,000 Pa;
d) spraying the side surfaces of the semiconductor wafer with water at a pressure no greater than 20,000 Pa;
e) dipping the semiconductor wafer into an aqueous alkaline cleaning solution;
f) cleaning the semiconductor wafer between rotating rollers with a supply of water;
g) spraying the semiconductor wafer with water; and
h) drying the semiconductor wafer.
2. The method recited in claim 1 , wherein steps b) through d) are performed in the first cleaning module, step e) is performed in a second cleaning module, and steps f) and g) are performed in a third cleaning module.
3. The method recited in claim 1 , wherein steps b) through g) include holding the semiconductor wafer vertically upright and rotating the semiconductor wafer about a center thereof.
4. The method as recited in claim 1 , wherein:
step b) is performed in a time period in a range of 10 s to 30 s,
step c) is performed in a time period in a range of 20 s to 30 s,
step d) is performed in a time period in a range of 1 s to 10 s,
step e) is performed in a time period in a range of 40 s to 60 s,
step f) is performed in a time period in a range of 10 s to 30 s, and
step g) is performed in a time period in a range of 5 s to 10 s.
5. The method recited in claim 1 , wherein an elapsed time from the transferring of the semiconductor wafer from the polishing plate in step a) through complete drying of the semiconductor wafer in step h) is no greater than 360 s.
6. The method as recited in claim 1 , further comprising discharging the wafer dried during step h) after a cycle time of no more than 75 s.
7. The method recited in claim 1 , wherein the cleaned semiconductor wafer has a diameter in a range of 200 mm to 450 mm.