Method for Making Convex Wafers
Original Publication Date: 1981-Jan-01
Included in the Prior Art Database: 2005-Feb-10
The use of wafers whose front surface is convex is increasing in importance in certain device applications. A method for making wafers with convex front surfaces has three basic elements: (1) The fiducial marking system is selected so that the wafer front and back sides are symmetrical and indistinguishable before laser scribing, as shown in the figure. (2) Device quality surfaces are generated on both sides of the wafers using free polishing techniques. (3) The sense of wafer warpage is measured after polishing, and the convex surface is laser scribed to identify the front side at a convenient and standard location.