Photolithographic dose determination by diffraction of latent im

Details Photolithographic dose determination by diffraction of latent im Photolithographic dose determination by diffraction of latent im

1994-05-12

1995-12-19

Duda, Kathleen

Radiation imagery chemistry: process, composition, or product th

Including control feature responsive to a test or measurement

430311, 430396, 2504911, G03F 720

Patent

active

054767385

ABSTRACT:
A method of determining quantitatively the exposure levels for photoresists in semiconductor photolithography employs a specially designed grating pattern on a mask. The mask is first used to expose a series of LIM image gratings of different dosages. Then a normal plane wave at a longer wavelength is incident on these gratings one by one, and some nonzero order diffraction efficiency of the grating is measured to determine quantitatively the correct dosage to be used. This method can make a determination of exposure dosage, without knowledge of underlying film thickness and refractive index, and handle either resist thickness change or underlying film thickness/refractive index change or both.

REFERENCES:
patent: 4308586 (1981-12-01), Coates
patent: 4640619 (1987-02-01), Edmark, III
patent: 4670650 (1987-06-01), Matsuzawa et al.
patent: 4890239 (1989-12-01), Ausschnitt et al.
patent: 4982226 (1991-01-01), Takahashi
patent: 5124927 (1992-06-01), Hopewell
Wittekoek, S.; Van Der Werf, J.; and George, R. A.; "Phase Gratings as Wafer-stepper Alignment Marks for all Process Layers", Optical Microlithography, SPIE vol. 538 (1985), pp. 24-31.
Yamashita, K., Nomura, N., Kubow, K, Yamada, Y. and Suzuki, M., "Heterodyne Holographic Nanometer Alignment for a Half-Micron Wafer Stepper", Optical/Laser Microlithography III, SPIE vol. 1264 (1990), pp. 219-226.
Hickman, K. C., Gaspar, S. M., Bishop, K. P., Naqvi, S. S. H., McNeil, J. R., Tipton, G. D., Stallard, Draper, B. R., Draper, B. L., "Use of Diffracted Light from Latent Images to Improve Lithography Control", Integrated Circuit Metrology, Inspection, and Process Control V, SPIE vol. 1464 (1991), pp. 245-257.
Adams, Thomas E., "Applications of Latent Image Metrology in Microlithography", Integrated Circuit Metrology, Inspection, and Process Control V, SPIE, vol. 1464 (1991), pp. 294-312.
Ota, Kazuya; Magome, Nobutaka; and Nishi, Kenji; "New Alignment Sensors for Wafer Stepper" Optical/Laser Microlithography IV SPIE, vol. 1463 (1991), pp. 304-314.
Katagiri, Souichi; Moriyama, Shigeo; and Terasawa, Tsuneo; "Alignment Technique Using Wafer Rear Surface", Optical/Laser Microlithography V SPIE, vol. 1674 (1992) pp. 509-516.
Bayer, T. and Makosch, G. "Photolithographic Process Control by Optical Phase Monitoring of Latent Images in Photoresist", IBM Technical Disclosure Bulletin vol. 34 No. 10A Mar. 1992.
Korth, H. E., "Method of Directly Measuring Line Width Deviations", IBM Techical Disclosure Bulletin vol. 34, No. 2, Jul. 1991.

Affiliated with

Also associated with

Rating

Photolithographic dose determination by diffraction of latent im does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Photolithographic dose determination by diffraction of latent im, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photolithographic dose determination by diffraction of latent im will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-991256