Abstract: A measurement system is presented for detecting the presence of one or more harmful chemical species within one or more chambers of a semiconductor wafer processing device. Chemical species of interest include oxygen (O.sub.2), nitrogen (N.sub.2), moisture (H.sub.2 O), and organic compounds associated with photoresist processing. Such organic compounds include isopropyl alcohol (CH.sub.3 CH(OH)CH.sub.3), acetone (CH.sub.3 COCH.sub.3), and ethyl-3-ethoxy propionate (C.sub.7 H.sub.14 O.sub.3). Candidate semiconductor wafer processing devices include evaporation, sputtering, and low pressure chemical vapor deposition (LPCVD) devices.

Abstract: A device is provided for aligning a laser. For example, such a device could be used to align a laser as part of a particle measurement device in a semiconductor process tool. The device consists of a rigid member with alignment marks which define the intended point of impingement of a beam emitted from the laser. The laser is moved to allow the emitted laser beam to extend upon the alignment device and impinge upon the alignment marks. When the laser beam impinges upon alignment marks, preferably formed near the center of the alignment device, the laser is determined to be in proper alignment. The device is configured having a outer circumference equal to the terminating element which the device replaces during the alignment procedure. The device is then removed from the semiconductor process tool and the terminating element, either a beam stop or a photodiode detector, is re-inserted. A procedure utilizing relatively few steps for properly aligning the laser is thereby provided.