Arrayed microcolumn operation with a wafer-scale Einzel lens

摘要

Microcolumn has been demonstrated as a promising technology for the next generation lithography with high resolution and high throughput capabilities. In previous works, arrayed microcolumn operations as single column modules have been demonstrated. Arrayed microcolumn structure based on a wafer-scale Einzel lens has been fabricated and successfully demonstrated. Each microcolumn consists of an electron field emitter, micro-lenses, double octupole deflectors put on a wafer-scale Einzel lens. For the ideal alignment of 12 microcolumns, the laser diffraction method with double laser beam was employed and proved to be satisfactory. For the first operation, two microcolumns on the wafer-scale Einzel lens was assembled and operated with identical beam energy and focusing voltage and the specimen current images of Si grid sample were obtained by the arrayed microcolumns. Samples were installed under the columns with a working distance of 0.6 mm and the sample current was measured to be ～0.3 nA for both columns. Arrayed microcolumns based on a wafer-scale Einzel lens were evaluated in two operation conditions: (1) Independent operation in which the column operation was performed independently except Einzel lens. (2) Parallel and simultaneous operation in which all the voltages were applied from a set of power supplies. In these two different operation methods, no meaningful difference was observed. Also, the variation of other operation parameters keeping the beam energy constant did not give and significant change in the test image. In this paper, preliminary results of arrayed microcolumn with a wafer-scale Einzel lens and the possibility of the full wafer-scale microcolumn array will be presented in detail.