Paper
8 December 1995 Embedded attenuating phase-shift mask: printability of defects
Rajeev R. Singh, Alvina M. Williams, Chi-Min Yuan, Greg P. Hughes, G. Foss, Ronald M. Martino
Author Affiliations +
Abstract
The manufacture of an embedded attenuating phase shift mask (E-APSM) is the simplest among all the phase shift mask (PSM) types. This is because an E-APSM provides the necessary attenuation and phase shift requirements using a single layer absorber film. Therefore, the tasks of patterning, inspection and repair are much easier to accomplish than for a multi-level quartz etched or SOG/SiO2 coated PSM. Reports in literature indicate that an E-APSM, also referred to as a single-layer half-tone PSM, is likely to be used for the contact masking layer in the manufacture of 64 M-bit DRAMs. It has also been stated that defect-free E-APSMs will be manufactured using currently available mask making tools. Therefore, it could be inferred that the defect specifications for an E-APSM are expected to be the same as that for a standard chrome mask. Perturbation modeling studies indicate that this should be true. An experimental study of repair and printability of defects on contacts on an E- APSM, using a chrome-based embedded attenuating film was performed. Exposures were made on an i-line stepper with NA equals 0.6 and sigma equals 0.6. Oxide wafers were coated with a high contrast i-line resist and the contact pattern was transferred into the oxide using a decorative etch process. Measurements were made using a SEM. The wafer results were also compared with printability studies done using an aerial imaging measurement system. The results of repairs done on 1 micrometer size defects on 2 micrometer size contacts indicate that the currently available laser repair tool was successful in restoring the lithographic performance of the E-APSM contacts to an acceptable level.
© (1995) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Rajeev R. Singh, Alvina M. Williams, Chi-Min Yuan, Greg P. Hughes, G. Foss, and Ronald M. Martino "Embedded attenuating phase-shift mask: printability of defects", Proc. SPIE 2621, 15th Annual BACUS Symposium on Photomask Technology and Management, (8 December 1995); https://doi.org/10.1117/12.228181
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Photomasks

Critical dimension metrology

Semiconducting wafers

Manufacturing

Phase shifts

Lithography

Oxides

RELATED CONTENT

Manufacturability of a 0.18-um OPC technology
Proceedings of SPIE (August 25 1999)
Millennium maskmaking
Proceedings of SPIE (April 28 1999)
Line width verification for 0.18 and 0.25 um design...
Proceedings of SPIE (August 25 1999)

Back to Top