Sub-100 nm pattern generation by means of focused electrons, ion projection and x-ray lithography

Fabrication of nanoelectronic devices requires a lithography, which realizes besides resolution also application related features e. g. overlay, chip field size, pixel transfer rate, process stability and so on. As primary pattering procedure e-beam writing is established in many laboratories for research and development. E-beam writing meets already most of the requirements for nanolithography, but there are a few drawbacks like the proximity-effect and low pixel transfer rate. In order to overcome these disadvantages printing methods like X-ray lithography and demagnifying ion projection are very promising. A closer look to these printing methods shows that concerning application relevant requirements, they both have complementary characteristics. This is valid for special aspects of mask technology (lx-mask vs. open stencil mask), for overlay aspects (mask vs. lens distortion), and for alignment optical mechanized vs. electrical). With particular respect to device related performanc e data we find again complementary results: chip field size, illumination homogenity, radiation damage. In this paper recent results of e-beam writing for X-ray mask patterning and for direct write applications are presented. In addition, investigations of both printing methods demonstrate clearly the capability to enter the sub- 100 nm range. For X-ray lithography questions of mask technology and proximiry reduction have to be solved. Concerning demagnifying ion projection main focus is set on homogenety improvement and mask load