MA 6 BA 6 Mask

The SUSS MicroTec MA 6 / BA 6 is a contact mask aligner used for photolithography. The machine is designed for front-side and back-side alignment exposure of substrates. The system combines the MA 6 mask aligner role with the BA 6 bond aligner or back-side alignment configuration. The MA 6 / BA 6 supports wafer sizes from 2 to 6 inches. The equipment is part of the mature-node lithography tool class used in research, development, and small-volume production.^{[2][3][4][9][1]}

Some units are configured with top-side alignment (TSA) and back-side alignment (BSA) capability. Configurations may include an optical BSA system, a DVM6 microscope, and UV400 optics that support exposure wavelengths of 365 nm and 405 nm. Objectives of 5x, 10x, and 20x are used with the alignment microscope. The system can operate in soft, hard, and vacuum contact modes depending on tooling. A 350 W lamphouse and a Generation 2 CIC power supply are used on typical systems. The tool operates on 230 V, 50/60 Hz supply with a nominal load of 1500 VA in some configurations.^[4][9][3]

The MA 6 / BA 6 sits at the lithography step in a micro-fabrication process flow. Photolithography using a mask aligner defines the pattern that is later etched, implanted, or deposited onto the substrate. Contact lithography is typically used for feature sizes that are larger than those produced by projection steppers, and it is common in MEMS, microfluidics, and compound semiconductor fabrication. The tool is used for patterning individual die as well as full wafers.^[1]

In a typical process, the substrate is first cleaned and coated with photoresist, then loaded onto the aligner chuck. After alignment and exposure, the substrate moves to a develop step, followed by etching or other pattern transfer processes. The tool may be paired with wafer bonding equipment, since the back-side alignment capability allows patterns on one wafer to be aligned to features on the back side of another wafer before bonding.^[1]

The MA 6 / BA 6 is used for contact photolithography in research and production environments. The tool is used for patterning of MEMS devices, microfluidic structures, and other microsystems. The back-side alignment capability supports double-sided lithography, which is important for devices that require patterns on both sides of a substrate. The system can also be used for compound semiconductor and silicon device fabrication.^[1][4]

Applications include patterning of photoresist for subsequent etching, electroplating, or liftoff processes. The wafer bonding context is a notable application, since the aligner works with bonders to align wafers before bonding. The support for substrates up to 6 inches makes the tool suited for small-format production and prototyping.^[1][4]