In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 31, No. 12S ( 1992-12-01), p. 4161-
Abstract:
This paper presents a t hrough- t he- l ens (TTL) alignment, called s eparated mar k T TL alignment (SMART), applied to a KrF excimer laser lithography system. This SMART optical system does not require any complicated compensation mechanisms for longitudinal chromatic aberration. Several advanced methods for SMART optics to obtain higher overlay accuracy, such as optical heterodyne interferometry, real-time alignment system, and alignment signal processor, have been developed and adopted. The performance of such an improved SMART in an excimer laser lithography system was experimentally evaluated using d ynamic r andom a ccess m emory (DRAM)-processed wafers. An overlay accuracy of 0.05 µm (3σ) has been achieved.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.31.4161
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
1992
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7
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