In:
Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena, American Vacuum Society, Vol. 26, No. 6 ( 2008-11-01), p. 2127-2130
Abstract:
With continuous reduction in linewidth of the VLSI devices, the pattern integrity of photomasks becomes considerably more important than ever. Consequently, requirement for the defect repair technology on photomasks is more severe and strict. Focused ion beam (FIB) technology has been widely used for defect repairing in photomask industry. Therefore, the performance of the FIB mask repair tool has to be improved especially in repair accuracy and precision. The FIB repair processes are classified into two kinds; one is additive repair using FIB induced deposition for missing patterns, the other is subtractive repair using gas assisted FIB etching for extra patterns. In both processes, precursor gas is applied onto the processing area through a small nozzle. Thus, the repair processes are controlled by the FIB irradiation and the precursor gas supply. Important characteristics of the repairs, such as size, shape, and placement of the repair area, are defined by the FIB scanning control. As conventional FIB systems used raster type of beam scanning for the repair processes, the size, shape, and placement could be controlled with the unit of pixel size (typically about 6–12nm). However, in order to satisfy the recent requirement, more precise beam control is needed. The authors have developed a vector scanning system to meet the requirement. The vector scanning system enables us to control ion beams more precisely and more arbitrarily. Furthermore, unicursal beam scanning can be applied to the repair processes, which minimizes beam blanking times. By adopting the vector scanning, repair precision is improved. Additionally, sidewall angle of the repair region is also improved because the repair shape is formed without beam blanking.
Type of Medium:
Online Resource
ISSN:
1071-1023
,
1520-8567
Language:
English
Publisher:
American Vacuum Society
Publication Date:
2008
detail.hit.zdb_id:
3117331-7
detail.hit.zdb_id:
3117333-0
detail.hit.zdb_id:
1475429-0
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