In:
Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena, American Vacuum Society, Vol. 24, No. 6 ( 2006-11-01), p. 2631-2635
Abstract:
A new method for the actinic inspection of defects inside and on top of extreme ultraviolet (EUV) lithography multilayer-coated mask blanks is presented. The experimental technique is based on photoemission electron microscopy supported by the generation of a standing wave field inside and above the multilayer mask blank when illuminated near the resonance Bragg wavelength at around 13.5nm. Experimental results on programed defect samples based on electron beam lithographic structures or silica balls overcoated with an EUV multilayer show that buried defects with a lateral size down to 50nm are detectable. Furthermore, phase structures as shallow as 6nm in height on a programed phase grating sample have been detected by this technique. The contrast of the phase defect structures has shown to be strongly dependent on and controlled by the phase of the standing wave field at the mask blank surface, and thus can be optimized by tuning the inspection wavelength.
Type of Medium:
Online Resource
ISSN:
1071-1023
,
1520-8567
Language:
English
Publisher:
American Vacuum Society
Publication Date:
2006
detail.hit.zdb_id:
3117331-7
detail.hit.zdb_id:
3117333-0
detail.hit.zdb_id:
1475429-0