The Quintel Q 4000-6 is a 1:1 contact mask alignment system that uses broad band UV to perform conventional optical photolithography. The system accepts substrates sized from 50 to 150 mm, as well as pieces.  The system is outfitted with infrared (IR) for thru wafer imaging to enable frontside to backside alignment.  Overlay accuracy for frontside to backside is approximately 1 to 2 mm, while frontside to frontside alignment is typically 0.5 mm.  Exposures can be carried out in both contact and proximity mode.  The Quintel mask aligner system is capable of resolving 1 mm nominal features.

A contact printer involves putting a mask in direct contact with the wafer. In proximity mode a small air gap (~10 to 50 mm) is retained between the mask and wafer. The mask pattern is directly imaged onto the photoresist on the wafer in both cases. The resolution is roughly given by the square root of the product of the wavelength and the gap distance. Therefore contact printing provides the best resolution, but since the wafer and mask are in direct contact, defects are more prevalent.