While CMOS processor ICs have used step-and-repeat photolithography techniques for some time, the contact lithography it largely displaced has remained useful in the development of more exotic semiconductor technology, such as certain RFICs, optical devices, and MEMS. This has created a new demand for both new and remanufactured contact mask aligners, shown in the figures.

(click for full image)

(click for full image)

Quintel and Neutronix were two individual companies that respectively served the new and remanufactured segments. Quintel was acquired by Neutronix, which now operates as Neutronix-Quintel and still supplies both segments. The remanufactured units are Cannon PLA and MPA machines. Approximately 15% of the new equipment is custom-designed.

According to Brett Arnold, president, the commercial availability of these machines benefits the suppliers of legacy products, such as RF devices for military applications. Demand for these devices is often moderate, but steady, making the lower cost of contact mask aligners a sensible alternative to stepping lithography machines that are faster but more expensive.

For these same reasons, contact lithography is also a good choice in research projects. Neophotonics, for example, uses projection lithography in the development of its solid-state optical switches. The switches are formed on a polymer; after fabrication, they are connected through wires to an electronic control housed in a separate enclosure.

Another benefit contact lithography provides to researchers is the use of partial-wafer planarization. Stepping lithography requires full planarization of the wafer, which is wasteful when only a small region of the wafer is used for an experiment.

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