Abstract
We present a sensitive technique for determining the optical and thermal properties of solids, surfaces and thin films. This technique, photothermal displacement Spectroscopy, is based on the detection of the thermal expansion of a sample upon absorption of electromagnetic radiation. The technique is well suited for in situ ultrahigh vacuum studies and for experiments where wide temperature ranges are required. We show that surface and bulk optical absorption can be distinguished and that surface absorptions of αL=10−6/W of incident power can be measured. The theoretical basis of the signal generation is given, and excellent experimental and theoretical agreement is demonstrated. The implications of our findings to imaging and microscopy are discussed.
Similar content being viewed by others
References
E.g., reviews by H. Lüth: Appl. Phys.8, 1 (1975)
G. Heiland, W. Mönch: Surf. Sci.37, 30 (1973)
G. Chiarotti: Recent Developments in Condensed Matter Physics1, 633 (Plenum Press, New York 1981) and references therein
A. Hordvick: Appl. Opt.16, 2827 (1977)
Other photothermal techniques include photoacoustic spectroscopy [see, for example:Optoacoustic Spectroscopy and Derection, ed. by Y.-H. Pao (Academic Press, New York 1977); W.B. Jackson, N.M. Amer: J. Appl. Phys.51, 3343 (1980)]; photothermal deflection spectroscopy [W.B. Jackson, N.M. Amer, A.C. Boccara, D. Fournier: Appl. Opt.20, 1333 (1981)]; and photothermal radiometry [S.O. Kanstad, P.-E. Nordal: Appl. Surf. Sci.6, 372 (1980)]; among others. However, none of those techniques meet all the requirements for experiments which require ultrahigh vacuum, high spatial resolution, cryogenics or the high temperatures necessary for annealing many materials
S. Ameri, E. A. Ash, V. Neumann, C. R. Petts: Electron. Lett.17, 337 (1981)
See, for example: I. Ohlidal, F. Lukes, K. Navratil: J. Phys. (Paris)38, C5–77 (1977)
Y.S. Touloukian, R.W. Powell, C.Y. Ho, M.C. Nicolaou: “Thermal Diffusivity”,Thermophysical Properties of Matter, Vol. X (IFI/Plenum Press, New York 1973)
A.C. Boccara, D. Fournier, J. Badoz: Appl. Phys. Lett.36, 130 (1980)
A.C. Boccara, D. Fournier, W. Jackson, N.M. Amer: Opt. Lett.5, 377 (1980)
M.A. Olmstead, N.M. Amer: J. Vac. Sci. Technol. B1, 751 (1983)
E.D. Huber, S.O. Sari: Rev. Sci. Instrum.50, 438 (1979)
W. Nowacki:Thermoelasticity (Pergamon Press, Oxford 1962)
J.D. Jackson:Classical Electrodynamics (Wiley, New York 1975) p. 132
S.M. Sze:Physics of Semiconductor Devices (Wiley, New York 1981)
American Institute of Physics Handbook, ed. by D.E. Gray (McGraw-Hill, New York 1972)