This MJB 3 UV400 model is equipped with a 350W mercury lamp and a high-resolution optical system. Primary exposure wavelengths are 350-450nm. The instrument can perform exposures in vacuum contact, hard contact, and soft contact modes. Resolutions of 2.0 µm (soft contact mode), 1.0 µm (hard contact mode) and <0.6 µm (vacuum contact) can be achieved under optimal conditions. The subassemblies of the MJB 3 include a high-precision alignment stage accurate to 0.1 µm and a brightfield microscope equipped with 5X, 10X and 25X objectives. The mask aligner can accept substrates of various sizes up to 3 inches in diameter and 3mm in thickness, and masks up to 4 inches in diameter.

Exposure is performed in constant intensity mode CI-1 (365 nm) or CI-2 (405 nm). The controller monitors the lamp intensity measured by channel 1 (CI-1 mode) or channel 2 (CI-2 mode) of the feedback sensor and varies the power supplied to the lamp to maintain the intensity selected by the operator. Modes CI-1 and CI-2 are user-selectable on the front panel of the CIC power supply.