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Composition analysis of thin AlxGa1−xAs layers with TEM and SIMS

  • A. F. de Jong (a1) and K. T. F. Janssen (a1)


In this paper two methods for measuring aluminum compositions in very thin (1.5–15 nm), individual AlxGa1–xAs layers are investigated. The transmission electron microscopy (TEM) thickness-fringe method uses the bright-field extinction fringes from a small, cleaved 90° wedge imaged in a [100] orientation. By comparing calculated and experimental extinction fringes, compositions are determined with a sensitivity in x of 0.03, in layers with a thickness of 3.5 nm. With secondary ion mass spectrometry (SIMS), compositions in AlxGa1–xAs layers with a thickness of 15 nm are measured with an accuracy in x between 0.02 and 0.05. Thicker layers (1 μm) with a composition known from x-ray diffraction measurements are used as a reference for both methods. Subsequently, TEM results are compared with SIMS and the reference measurements. The overall agreement is good, but for 0.25 < x < 0.65, the values of x found by TEM are systematically 0.05 too low. Using the SIMS and reference measurements as a calibration, compositions can be determined by TEM with an accuracy between 0.03 (low x) and 0.05 (high x) in layers as thin as 1.5 nm.



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1Dingle, R., Festkörperprobleme 15, 21 1975).
2Duggan, G., Ralph, H.I., and Moore, K. J., Phys. Rev.B 32, 8395 (1985).
3Shealy, J. R., Schaus, C. F., and Wicks, G.W., Appl. Phys. Lett. 47, 125 (1985).
4Fewster, P. F., in Thin-film Growth Techniques for Low-Dimensional Structures, edited by Farrow, R. F. C. (Plenum Publ. Corp.), p. 417.
5Bartels, W. J. and Nijman, W., J. Cryst. Growth 44, 518 (1978).
6Loretto, M. H., in Microscopy of Semiconducting Materials 1987 (Inst. Phys. Conf. Ser. 87, London, 1987), p. 633.
7Kakibayashi, H. and Nagata, F., Jpn. J. Appl. Phys. 25,1644 (1986).
8Eaglesham, D. J., Hetherington, C. J. D., and Humphreys, C. J., in Mater. Res. Soc. Symp. Proc. 77, 473 (1987).
9Ou, H.J., Tsen, S.C., Tsen, K.T., Cowley, J.M., Chyi, J.I., Salvador, A., and Morkoç, H., Appl. Phys. Lett. 54, 1454 (1989).
10Boudewijn, P.R., Leys, M. R., and Roozeboom, F., Surf. Interface Anal. 9, 303 (1986).
11McPhial, D.S., Dowsett, M. G., Fox, H., Houghton, R., Leong, W.Y., Paeker, E. H. C., and Patel, G. K., Surf. Interface Anal. 11, 80 (1988).
12Van Dyck, D., Adv. in Electr. and El. Phys. 65, 295 (1985).
13Coene, W. and Van Dyck, D., Ultramicroscopy 15, 41 (1984); ibid., p. 287.
14Doyle, P. A. and Turner, P. S., Acta Cryst. A24, 390 (1968).
15International Tables for X-ray Crystallography (Kynoch Press, Birmingham, 1962), Vol. Ill, p. 232.
16Humphreys, C. J.and Hirsch, P. B., Phil. Mag. 18, 115 (1968).
17Radi, G., Acta Cryst. A26, 41 (1970).
18Matsushita, T. and Hayashi, J., Phys. Stat. Sol. A41, 139 (1977).
19Adachi, S., J. Appl. Phys. 58, Rl (1985).
20Reid, J. S., Acta Cryst. A39, 1 (1983).
21Janssen, K. T. F. and de Jong, A. F. (to be published).
22Boothroyd, C. B. and Stobbs, W. M., Ultramicroscopy 26, 361 (1988).
23Zuo, J. M., Spence, J. C. H., and O'Keeffe, M., Phys. Rev. Lett. 61, 353 (1988).

Composition analysis of thin AlxGa1−xAs layers with TEM and SIMS

  • A. F. de Jong (a1) and K. T. F. Janssen (a1)


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