| 摘要 |
<p>A wafer holder (15) including a wafer stage (1) and a wafer stage outer-ring (2) surrounding the wafer stage (1) wherein the wafer stage (1) has a diameter smaller than the diameter of a wafer (5) loaded on the wafer stage (1), the wafer stage outer-ring (2) has an inner diameter at the upper side of the outer-ring (2) which is larger than the diameter of the wafer (5) loaded on the wafer stage (1), and the upper surface of the outer-ring (2) lies above the upper surface of the wafer (5) loaded on the wafer stage (1).</p> |
