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Electrical and Computer Engineering

University of South Carolina

Single crystals

Publication Year

Articles 1 - 3 of 3

Full-Text Articles in Engineering

Crystal Growth, Characterization And Anisotropic Electrical Properties Of Gase Single Crystals For Thz Source And Radiation Detector Applications, K. C. Mandal, C. Noblitt, M. Choi, A. Smirnov, R. D. Rauh Jan 2005

Crystal Growth, Characterization And Anisotropic Electrical Properties Of Gase Single Crystals For Thz Source And Radiation Detector Applications, K. C. Mandal, C. Noblitt, M. Choi, A. Smirnov, R. D. Rauh

Faculty Publications

The single crystal growth of large semi‐insulating GaSe by the vertical Bridgman technique using zone‐refined selenium (Se) and HP gallium (Ga) is described. The grown crystals (up to 10 cm long and 2.5 cm diameter) have been characterized thoroughly by X‐ray diffraction (XRD), energy dispersive analysis by x‐rays (EDAX), optical absorption/transmission, X‐ray photoelectron spectroscopy (XPS), charge carrier electrical property measurements, second harmonic test, and radiation detection measurements.


Algan/Gan Heterostructure Field-Effect Transistors On Single-Crystal Bulk Aln, X. Hu, J. Deng, N. Pala, R. Gaska, M. S. Shur, C. Q. Chen, J. Yang, Grigory Simin, M. A. Khan, J. C. Rojo, L. J. Schowalter Feb 2003

Algan/Gan Heterostructure Field-Effect Transistors On Single-Crystal Bulk Aln, X. Hu, J. Deng, N. Pala, R. Gaska, M. S. Shur, C. Q. Chen, J. Yang, Grigory Simin, M. A. Khan, J. C. Rojo, L. J. Schowalter

Faculty Publications

We report on the performance of AlGaN/GaN/AlN heterostructurefield-effect transistors(HFETs) grown over slightly-off c-axis, single-crystal, bulk AlN substrates. Dc and rf characteristics of these devices were comparable to HFETs grown on semi-insulating SiC. The obtained results demonstrate that bulk AlN substrates are suitable for fabricating high-power microwave AlGaN/GaN transistors.


Near-Band-Edge Photoluminescence Of Wurtzite-Type Aln, E. Kuokstis, J. Zhang, Q. Fareed, J. W. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur, C. Rojo, L. Schowalter Sep 2002

Near-Band-Edge Photoluminescence Of Wurtzite-Type Aln, E. Kuokstis, J. Zhang, Q. Fareed, J. W. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur, C. Rojo, L. Schowalter

Faculty Publications

Temperature-dependentphotoluminescence(PL)measurements were performed for A-plane and C-plane bulk AlN single crystals and epitaxial layers on sapphire. A strong near-band-edge (NBE) emission and deep-level luminescence were observed. At low excitations, the emission spectra are dominated by free and bound excitonic transitions and their LO-phonon replicas. At high excitations, the broadening and redshift of the NBE band is attributed to dense electron–hole plasma formation. The PL spectra differences of bulk single crystals and epilayers is explained by the electron–hole plasma expansion peculiarities.