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This paper presents different low-temperature and high-throughput LIGA-like processes for the batch fabrication of metal micro systems that use long nano- or microwires perpendicularly rising from a substrate. First, circuit paths and seed layers are fabricated applying standard UV lithography and PVD. Second, three lithography techniques are used, namely ion track lithography, enhanced UV lithography and aligned x-ray lithography, to structure 20–400 µm thick polymer films. Ion track lithography is only used to fabricate extremely high aspect ratio cylindrical pores with 0.1–1 µm diameter and 20–100 µm length. The aligned UV and x-ray lithographies are employed to structure templates for various micro system components. Third, these polymer templates are filled using low-temperature electroplating processes transferring the polymer openings into metal structures. Finally, the polymer is dry etched to release all metal structures. These structures are applicable in future accelerometers and gas flow sensors. Using five configurations to define five different functional structures, we demonstrate fabrication processes applying the three different types of lithography. The main aspects concern the combination of both standard lithography techniques and especially developed lithography techniques. Furthermore, these aspects comprise the use of structures created by lithography for high aspect ratio polymer templates and multilayer electroplating with varying aspect ratios. The growth in place of nanowire arrays and micropillars along with surrounding structures is the key feature for low-temperature large-scale micro-nano integration technology without harmful transfer technologies.

An in situ synthesis process for nanowire arrays was used to fabricate a customized field emitter array for use as a nonthermal electron source in an ionization gauge. The wire arrays fabricated with this process had a density of 1.6 × 106 cm−2 using optimized deposition of the wires in template foils on predefined electrodes. The diameter of the wires varied from 100 to 400 nm and their length ranged from 8 to 100 μm. This method can enclose with nanowires a wide area of predefined electrodes, and is possible for areas larger than 3 cm2. Further, the cylindrical shape of the nanowires was modified into a conical geometry to achieve improved thermomechanical stability.

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