Journal of Vacuum Science & Technology B, Vol.24, No.6, 2945-2950, 2006
Sub-100-nm lithography with miniature electron beam columns
Miniature low-voltage electron beam columns are well suited for low cost imaging and high throughput direct-write lithography applications. Previous generations of miniature columns have demonstrated high-resolution imaging and proof-of-concept lithography. However, those columns suffered from difficult fabrication techniques and costly assembly, making them impractical for broad application. A new type of miniature electron beam column has been developed with the goal of manufacturability using bonded stacks of batch fabricated silicon lenses and glass insulators. Bulk micromachining and integrated chip fabrication techniques facilitate the fabrication of columns with precise aperture-to-aperture alignment and high aperture circularity. The lens stacks are bonded to a multilayer ceramic package with embedded interconnects. This approach enables a small package that can include buried internal and external passive and active devices, ground planes, and controlled impedance-matched lines. The package is fully scalable for continued miniaturization, and can be easily designed to accommodate I X 4 or larger modules of individually correctable columns for arrayed operation. This article presents the first lithography results with these miniature columns over a beam energy range of 0.5-2 keV. Patterns were written into similar to 45 nm ZEP-520A resist using a raster-scan writing strategy. A nominal dose of 7 mu C/cm(2) yielded 90 nm isolated and 180 nm line-space patterns. High-resolution images resolved < 35 nm features. (c) 2006 American Vacuum Society.