Patent Number: 6,254,155

Title: Apparatus and method for reliably releasing wet, thin wafers

Abstract: In a type of end effector used for handling wafers in the semiconductor industry, the wafer is acquired by lowering the end effector until it almost touches the upper side of the wafer and then applying suction to lift the water into contact with a wafer contacting surface on the underside of the end effector. Release of the wafer is accomplished by relieving the suction or replacing it with a small overpressure. Wet thin wafers do not reliably release; the liquid spreads into a thin film between the upper side of the wafer and the wafer contacting surface, and the surface tension of this film causes the thin wet wafer to adhere to the wafer contacting surface. This problem is solved by affixing a sheet of a porous resilient material, such as open cell MYLAR.RTM., to the wafer contacting surface.

Inventors: Kassir; Salman M (Paso Robles, CA)

Assignee: Strasbaugh, Inc.

International Classification: B25J 15/06 (20060101); H01L 21/683 (20060101); H01L 21/67 (20060101); B25J 015/06 ()

Expiration Date: 07/03/2018