Mask Assembly and Wafer Tray
Original Publication Date: 1986-Jul-01
Included in the Prior Art Database: 2005-Mar-09
Semiconductor wafers and photolithographic mask assemblies are subject to particulate contamination and operator damage during storage and handling, which can cause the wafer or mask assembly to be rejected. An improved carrier tray has substantially reduced the number of defects caused by handling and particulate contamination. Mask assemblies, which typically include a photolithographic mask in contact with a wafer, a bias spring, retaining rings, and clips, were previously stored in a substantially vertical position in a rack. The assemblies were prone to contamination by airborne particulates and were difficult for operators to insert and remove.