Abstract: There is disclosed a vacuum contact printer and process for printing copy plates from master photomask plates depicting electronic circuitry.The printer embodies a vacuum-tight enclosure or casing, containing three vacuum chambers, two outside master and copy plate plenum chambers, and an intermediate main chamber. Retainers for the master and copy chambers hold and frame the master photomask and copy plates, respectively, and these retainers are mounted in confronting printing frames. The one of these printing frames which supports the master photomask plate is carried by a mounting plate fixed to an outside casing, and the other of the printing frames is carried by a swinging door of this casing. The master and copy photomask plates form partitions across the interior of the casing, and are positioned against flexible elastomeric framing seals, which complete these partitions.

Abstract: This invention relates to a printing frame for the exposure of printing plates comprising two closable components, flexible sheet means secured to one of said components and being adapted to press a printing plate and an original together and maintain them in close contact during exposure, and means for exerting air pressure on said flexible sheet means in order to press said printing plate and original together.

Abstract: A non-planar semiconductor wafer chuck having a plurality of outwardly extending channels in the chuck face and a plurality of vacuum/pressure ports extending through the chuck and communicating with the face thereof. When a semiconductor wafer is positioned with respect to an overlying photomask by the chuck, atmospheric pressure is applied to the centrally located port or ports and a vacuum is applied to the peripheral ports of the chuck. The resulting pressure differentials acting in concert with a surrounding vacuum chamber causes the central portion of the wafer to rise against the photomask while the peripheral portions of the wafer are drawn down into the channels. At this point in the operational sequence, the normally trapped nitrogen can escape through breaks in the peripheral seal between the mask and wafer which are formed by the downwardly extending wafer surface in each channel.