Abstract: A spatial photomask flipper provides up to four access gates for an unloading of a clamped photomask after its reorientation along a single photomask transfer axis. The clamping frames holding the photomask are secured by a locking control cam that prevents their inadvertent opening in any other but the two main flip orientations. The flipper is part of an automated system including a digital camera and an image recognition algorithm that interpret an arbitrary initial photomask loading orientation from a circumferential photomask identification number. An eventual pellicle on the photomask may be also automatically detected via a pellicle detection sensor. Alternately, the digital camera may be employed for pellicle detection together with a pellicle detection algorithm that processes the digital image for well known components of the pellicle such as the pellicle frame.

Abstract: A compact multiple diameter wafer testing device with a footprint of about 33 by 34 inches features on-chuck wafer calibration and integrated cassette-chuck transfer. It includes a five axes wafer handling system, a quick exchange chuck and a fixed through beam sensor fixed. Two of the five axes are provided by an X-Y stage, a third axis is provided by a rotary stage on top of the X-Y stage, a fourth axis belongs to a rotating effector and a fifth axis is provided by motion controlled pin lifters all combined with the X-Y stage. The quick exchange chuck may be easily changed for different wafer diameters and also calibrated by the through beam sensor. The through beam sensor provides on-chuck position calibration of the chucked wafers in conjunction with the X-Y stage and rotary stage. The compact wafer testing device handles wafers between six and twelve inches diameter.

Abstract: A pellicle correction factor is determined by comparing a first measurement of a reference photomask alone with a second measurement of that reference photomask through a reference pellicle protecting the mask layers of the photomask. A number of pellicle correction factors may be determined for different type pellicles and made accessible in pellicle correction factor lookup table of the system or supplied on a separate data storage medium. Raw Reflectance and/or Transmittance measurement data of a generic photomask through a generic pellicle is consecutively corrected for the measurement distorting effects of that pellicle by applying a matching one of the previously determined pellicle correction factors. The pellicle correction factor is preferably an attenuation signature across a predetermined measurement irradiation spectrum.