In:
Journal of Vacuum Science & Technology B: Microelectronics Processing and Phenomena, American Vacuum Society, Vol. 7, No. 6 ( 1989-11-01), p. 1583-1585
Abstract:
In the past, nearly all x-ray nanolithography (i.e., sub-100-nm linewidths) employed the CK x-ray line at 4.5 nm. This, in turn, necessitated near-zero gaps (to avoid diffraction) and carbonaceous masks (e.g., polyimide, which is subject to distortion). In order to use x-ray replication in the fabrication of multilevel devices and circuits that cover large areas (∼a few cm2) and have feature sizes well below 100 nm, we have turned to the CuL line at 1.3 nm. Masks consist of 1–1.5 μm thick Si or Si3N4 membranes and Au absorber patterns, 200 nm thick, which provide 10 db contrast. Focused-ion-beam-lithography (FIBL) with Be++ ions at 280 keV was used to produce quantum-effect-device patterns with minimum linewidths of ∼50 nm. These were replicated using the CuL line, indicating that photoelectrons are not a serious problem. The FIBL process [exposure of 300 nm-thick polymethylmethacrylate (PMMA), followed by Au electroplating] is high yield and much simpler than a trilevel electron-beam-lithography process designed to give comparable results. This is the first time FIBL has been used to make x-ray masks at sub-100-nm linewidths. Along with the device patterns, linear-zone-plate alignment marks were also written on the masks, to be aligned to corresponding marks on the substrate via an optical alignment scheme.
Type of Medium:
Online Resource
ISSN:
0734-211X
,
2327-9877
Language:
English
Publisher:
American Vacuum Society
Publication Date:
1989
detail.hit.zdb_id:
3117331-7
detail.hit.zdb_id:
1475429-0
Permalink