Growth and characterization of indium arsenide thin films
- 129 Downloads
The growth and characterization of indium arsenide films grown on indium phosphide substrates by the metal organic chemical vapor deposition (MOCVD) process is reported. Either ethyl dimethyl indium or trimethyl indium were found to be suitable in combination with arsine as source compounds. The highest electron mobilities were observed in films nucleated at reduced growth temperature. Scanning electron microscopy studies show that film nucleation at low temperature prevents thermal etch pits from forming on the InP surface before growth proceeds at an elevated temperature. Electron mobilities as high as 21,000 cm2V−1 sec−1 at 300 K were thus obtained for a film only 3.4 μm thick. This mobility is significantly higher than was previously observed in InAs films grown by MOCVD. From the depth dependence of transport properties, we find that in our films electrons are accumulated near the air interface of the film, presumably by positive ions in the native oxide. The mobility is limited by electrons scattering predominantly from ionized impurities at low temperature and from lattice vibrations and dislocations at high temperature. However, scattering from dislocations is greatly reduced in the surface accumulation layer due to screening by a high density of electrons. These dislocations arise from lattice mismatch and interface disorder at the film-substrate interface, preventing these films from obtaining mobility values of bulk indium arsenide.
Key wordsInAs InP transport accumulation
Unable to display preview. Download preview PDF.
- 1.B. Lequesne and T. Schroeder, “Magistor: a novel magnetoresistive speed sensor—design and analysis,” GMR report no. E3-85, May 31, 1988.Google Scholar
- 2.S. Takaoka, “Recent development of magnetoresistive devices and applications,” Circulars of Electrotechnical Laboratory No. 182, Tokyo (1974).Google Scholar
- 7.R. Schneider, K. Huang and B. W. Wessels, The preparation of heteroepitaxial InAs by OMVPE,” presented at the Third Biennial AMVPE Workshop, Brewster, MA, Sept. 21–23, 1987.Google Scholar
- 9.Model GS 3000, Emcore Corp., 35 Elizabeth Ave., Somerset, NJ, 08873.Google Scholar
- 11.J. P. Wiley, in Semiconductors and Semimetals, eds., R. K. Willardson and A. C. Beer, Academic Press, New York, Vol. 10, 1975, p. 91.Google Scholar
- 12.W. Zawadzki, in Handbook on Semiconductors, ed. T. S. Moss, North Holland, Amsterdam, Vol. 1, 1982, p. 713.Google Scholar
- 14.L. Salamanca-Riba, A. K. Ballal, D. L. Partin, J. Heremans, L. Green and B. K. Fuller, to be published.Google Scholar