Determining the optical constants of read-write sliders during flying-height testing

Applied Optics

Volumn 37, Issue 22, 1998, Pages 5116-5125

  De Groot, Peter ^a   Dergevorkian, Ara ^b   Erickson, Tod ^b   Pavlat, Russell ^b  

^a ZYGO CORPORATION   (United States)

^b Zygo Flying High Test Division   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 10444267694     PISSN: 1559128X     EISSN: 21553165     Source Type: Journal    
DOI: 10.1364/AO.37.005116     Document Type: Article

References (36)

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11. F. Muranushi, K. Tanaka, and Y. Takeuchi, The calculations for Table 1 also appear in the paper “Inter-ferometric measurement of disk/slider spacing: the effect of phase shift on reflection, ” by C. Lacey, R. Shelor, A. Cormier, and R. E. Talke, IEEE Trans. Magn. MAG-29, 3906-3910 (1993).
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13. M. Born and E. Wolf, we prefer to use the n + ik definition of the complex index, rather than the more common n − ik.
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19. G. Sommargren, Generally, it is not possible to calculate a film thickness as well as the optical constants from a single ellipsometric measurement; hence the need for three or more flying heights for proper n and k calibration. See, for example, R. M. A. Azzam and N. M. Bashara, Ellipsometry and Polarized Light (Elsevier, Amsterdam, 1987), p. 317.
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27. P. de Groot, L. Deck, J. Soobitsky, and J. Biegen, “Optical flying-height testing of magnetic read-write heads, ” in Lasers, Optics, and Vision for Productivity in Manufacturing I, C. Gorecki, ed., Proc. SPIE 2782, 47-57 (1996).
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34. P. de Groot, J. Biegen, L. Deck, and R. Smythe, “Calibration standard for optical gap measuring tools, ” U.S. patent 5, 724, 134 (3 March 1998).
35. P. de Groot, J. Biegen, L. Deck, and R. Smythe, A similar arrangement for establishing known gaps for calibration appears in U.S. patent 5, 220, 408 to M. Mager, entitled “Method and apparatus for calibration of optical flying-height testers” (15 June 1993).
36. P. de Groot, J. Biegen, L. Deck, and R. Smythe, Our technique does require an estimated value for the scattered light loss, in the form of the p factor. However, the effect of an incorrect p on the ZSE is small. It serves primarily to simplify comparison of our technique with traditional ellipsometry.