TEMPERATURE CONDITIONING OF A STAGE POSITION MEASUREMENT IN A MULTI BEAM INSPECTION TOOL

摘要

Scanning Electron Microscopes (SEM) can be used to image structures with a very high accuracy, for example in the region of several nanometers. Therefore, SEM systems can be used in semiconductor manufacturing facilities for monitoring patterning defects in lithographic processes. To increase the speed of e-beam SEM devices, a multiple beam inspection (MBI) tool has been proposed, which measures using multiple e-beams simultaneously. It is important that the MBI tool is maintained at a suitable working temperature. Therefore waier cooling is provided, based on a single water temperature strategy. A water supply cabinet (WSC) is used to supply cooling water to the system. The temperature of the water is control led by the water supply cabinet in a manner such that cooling performance is sufficient for most modules of the HM1 tool. However, for the stage position measurement (SPM) system- the temperature stability of the water provided by the water supply cabinet is not sufficient.