Can POU improve delta temperature on the wafer or “within wafer” uniformity?
• Delta temperature change on the wafer is a characteristic of the chuck. Every chuck has an inherent temperature distribution across the surface that is unique to its design. • The temperature distribution across the wafer reflects the temperature distribution of the chuck. For example, the edge temperature may differ from the center temperature. POU will not eliminate this problem but will maintain temperature within the design parameters of the chuck.
