Wafer Dome Rotation System for Plasma Sputter Etch Operations
Original Publication Date: 1985-Mar-01
Included in the Prior Art Database: 2005-Feb-18
A wafer dome of a sputter etch machine can be rotated to obtain uniform etch distribution in a plasma environment without the development of electrical arcing at the dome site. The arc suppression is achieved by placing two evenly spaced, grounded concentric domes 1 and 2 in the same rotation axis as the wafer dome. The outer shield 1 is grounded and is stationary. The center shield 2 and the wafer dome 3 rotate at the same speed from the same drive mechanism 4 and feed-through assembly 5. The shields 1 and 2 and the wafer dome 3 are isolated from each other by the proper use of non-conducting spacers. This maintains a fixed gap between the shields and the wafer dome. The spacing is important to the arc-suppression requirement and is dependant on such parameters as temperature, gas pressure, etc.