Eickhoff, M. Stutzmann, F. Bernardini, V. Fiorentini, V. Tilak, B. Schaff, andL. F. Eastman, J. Phys.: Condens. Matter 14, 3399. (2002). [6] T. Y. Chang,M. A. Moram, ...
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FIG. 2. HRXRD FWHM of (002) plane and (102) plane of GaN for different thicknesses of AlN interlayer between AlGaN/GaN heterostructure.
FIG.4. PL spectra of samples A, B, C and D recorded at room temperature. IV. CONCULSTION The insertion of the 1 to 3 nm AlN interfacial layer between AlGaN/GaN generates a dipole to increase the effective ∆EC, accompanied by a small increase in 2DEG density. The structure also decreases the alloy disorder scattering, thus improving the electron mobility. AlN-IL is essential to grow good quality HEMTs structures for high frequency applications. V. REFERENCES [1] H. Morkoc, S. Strite, G. B. Gao, M. E. Lin, B. Sverdlov, and M. Burns, [2] [3]
[4] 2
FIG.3 AFM images with 5x5 µm scan area of the samples With different AlN interlayers.
FIG.3 shows Atomic Force Microscopy (AFM) images with a 5x5 µm2 scan area obtained on the AlGaN layer surface of samples with different AlN layers. Randomly oriented terrace step suggest a step flow growth mode. While the step flow growth is beneficial, the defects on the surface are deleterious for device performance[7]. The growth mode creates a smooth surface morphology. The approximate step heights on samples A,B,C and D are determined as 0.38, 0.36, 0.22nm and 0.16nm respectively. The photoluminescence spectra for the samples, measured at room temperature, are shown in FiG.4. PL emission has been observed for both GaN and AlGaN.
[4]
[6] [7]
” J. Appl. Phys., 76, 1994, pp.1363-1398. Asif Khan, Krishnan Balakrishnan & Tom Katona. Nature Photonics, pp77 – 84 (2008). Z. Dridi, B. Bouhafs and P. Ruterana, ,” Semicond. Sci. Technol., 18, 2003, pp.850–856. T. Sasaki and T. Matsuoka, ,” J. Appl. Phys., 77, 1995, pp.192-200. .O. Ambacher, J. Majewski, C. Miskys, A. Link, M. Hermann, M. Eickhoff, M. Stutzmann, F. Bernardini, V. Fiorentini, V. Tilak, B. Schaff, andL. F. Eastman, J. Phys.: Condens. Matter 14, 3399 (2002) T. Y. Chang,M. A. Moram, C. McAleese, M. J. Kappers, and C. J. Humphreys ” J. Appl. Phys., 108, 123522 2010 , A.torabi, P.Ericson.E,J.Yarration and W.E.Hooke J.Vac.Sci Technol.B.20.1234 (2002)
