Investigation of some critical aspects of on-line surface measurement by a wavelength-division-multiplexing technique

Some critical aspects of a new kind of on-line measurement technique for micro and nanoscale surface measurements are described. This attempts to use spatial light-wave scanning to replace mechanical stylus scanning, and an optical fibre interferometer to replace optically bulky interferometers for measuring the surfaces. The basic principle is based on measuring the phase shift of a reflected optical signal. Wavelength-division-multiplexing and fibre Bragg grating techniques are used to carry out wavelength-to-field transformation and phase-to-depth detection, allowing a large dynamic measurement ratio (range/resolution) and high signal-to-noise ratio with remote access. In effect the paper consists of two parts: multiplexed fibre interferometry and remote on-machine surface detection sensor (an optical dispersive probe). This paper aims to investigate the metrology properties of a multiplexed fibre interferometer and to verify its feasibility by both theoretical and experimental studies. Two types of optical probes, using a dispersive prism and a blazed grating, respectively, are introduced to realize wavelength-to-spatial scanning.

[1]  J C Dainty,et al.  Linnik microscope imaging of integrated circuit structures. , 1996, Applied optics.

[2]  Anthony Dandridge,et al.  Elimination of drift in a single-mode optical fiber interferometer using a piezoelectrically stretched coiled fiber. , 1980, Applied optics.

[3]  N. Bobroff.  Recent advances in displacement measuring interferometry , 1993 .

[4]  Profile measurement of optically rough surfaces by fiber-optic interferometry. , 1993, Optics letters.

[5]  Ichirou Yamaguchi,et al.  Digital Hilbert transformation for separation measurement of thicknesses and refractive indices of layered objects by use of a wavelength-scanning heterodyne interference confocal microscope. , 2002, Applied optics.

[6]  Cho Jui Tay,et al.  In situ surface roughness measurement using a laser scattering method , 2003 .

[7]  I. Yamaguchi,et al.  Wavelength scanning profilometry for real-time surface shape measurement. , 1997, Applied optics.

[8]  David J. Whitehouse,et al.  Handbook of Surface and Nanometrology , 2002 .

[9]  A. Dandridge,et al.  Measurement of small phase shifts using a single-mode optical-fiber interferometer. , 1980, Optics letters.

[10]  David J. Webb,et al.  Extended-range, low coherence dual wavelength interferometry using a superfluorescent fibre source and chirped fibre Bragg gratings , 1997 .

[11]  D. Whitehouse,et al.  REVIEW ARTICLE: Surface metrology , 1997 .

[12]  Rui Zhang,et al.  Step-height measurement by means of a dual-frequency interferometric confocal microscope. , 2004, Applied optics.

[13]  Klaus Fritsch,et al.  Simple circuit for feedback stabilization of a single­ mode optical fiber interferometer , 1981 .

[14]  Atsushi Taguchi,et al.  Optical 3D profilometer for in-process measurement of microsurface based on phase retrieval technique , 2004 .

[15]  B. Bhushan,et al.  Measurement of surface topography of magnetic tapes by Mirau interferometry. , 1985, Applied optics.

[16]  Ian Bennion,et al.  High stability multiplexed fiber interferometer and its application on absolute displacement measurement and on-line surface metrology. , 2004, Optics express.