Abstract: A margin inspector for IC wafers includes an upper plate and a supporting portion. The upper plate, which is formed as a transparent plate, has a plurality of concentric circular segments thereon for establishing a set of reference lines to examine the periphery ring of the wafer located under the upper plate while in examining operation. The supporting portion connected with the upper plate is used to form a working space, between the supporting portion and the upper plate, for accommodating the wafer to be examined. By applying these inspecting lines, any deviation on the washout periphery ring of the wafer can be easily and correctly located by eyesight.

Abstract: A wafer-fetching sensing device for wafer storage apparatus uses a planar detection means to replace a conventional linear detection means to detect if a wafer is properly positioned at a desirable access level before being moved out of an access opening of the wafer storage apparatus by a robot. Wafer tilting and damage incident that might otherwise happen thus may be avoided. Only a correctly positioned wafer will be fetched. A warning signal will be generated when the wafer is not properly positioned so that preventive action may be taken to avoid wafer damage. Production yield thus may be increased.