@article{bishop_reynolds_molstad_stevie_barnhardt_davis_2009, title={On the origin of aluminum-related cathodoluminescence emissions from sublimation grown 4H-SiC(11(2)over-bar0)}, volume={255}, ISSN={["0169-4332"]}, DOI={10.1016/j.apsusc.2009.02.036}, abstractNote={The spatial origins of emissions from homoepitaxial 4H-SiC(112¯0) films have been investigated by cathodoluminescence, secondary ion mass spectrometry, and electron trajectory simulations. At 15 keV (300 K), the spectrum contained three peaks. The most intense peak corresponded (3.18 eV) to the nitrogen donor-to-valence band transition. The lesser two peaks at 2.94 eV and 2.75 eV involved aluminum and oxygen impurities, respectively; both impurities were determined to be in high concentrations in the film–substrate interfacial region. At 25 keV (300 K) the primary emission broadened into a band at ∼3.10 eV. Deconvolution revealed three peaks; the most intense emission was again the nitrogen donor-to-valence band transition. The remaining two peaks at 3.02 eV and 2.90 eV were consistent with transitions involving aluminum impurities. The former peak was not observed in the spectra obtained at lower electron beam energies and was correlated with the conduction band-to-aluminum acceptor level transition. Monte-Carlo simulations showed the origin of the 25 keV (300 K) spectrum was the film–substrate interface. An analysis of the aluminum impurity concentration in this region revealed that the cause of the 3.02 eV emission was a dramatic increase in the concentration of aluminum (3 × 1016 cm−3 to 1 × 1018 cm−3). The emissions comprising the 3.10 eV band were further investigated at 6 K and 25 keV. The difference in the intensity of the conduction band-to-aluminum acceptor level transition at 6 K and 300 K was attributed to thermal impurity ionization and the spike in the interfacial aluminum concentration previously described.}, number={13-14}, journal={APPLIED SURFACE SCIENCE}, author={Bishop, S. M. and Reynolds, C. L. and Molstad, J. C. and Stevie, F. A. and Barnhardt, D. E. and Davis, R. F.}, year={2009}, month={Apr}, pages={6535–6539} }
 @article{bishop_reynolds_liliental-weber_uprety_ebert_stevie_park_davis_2008, title={Sublimation growth of an in-situ-deposited layer in SiC chemical vapor deposition on 4H-SiC(1 1 (2)over-bar 0)}, volume={311}, ISSN={["1873-5002"]}, DOI={10.1016/j.jcrysgro.2008.09.200}, abstractNote={Homoepitaxial growths of 4H-SiC(1 1 2¯ 0) epitaxial layers have been achieved using chemical vapor deposition from 1250 to 1600 °C and two process routes: (1) with and (2) without the addition of SiH4 and C2H4 to the growth ambient. An activation energy of 3.72 eV/atom (359 kJ/mol) was determined for the former route and associated with either reactions in the gas phase or the potential barrier associated with the temperature-dependent sticking coefficient. The activation energy for the latter route was 5.64 eV/atom (544 kJ/mol), which is consistent with published values for SiC sublimation epitaxy. Sublimation dominated the growth process at temperature ⩾1600 °C. The same effect resulted in the in-situ deposition of a thin film during the heating stage of route (1). At 1450 °C this layer was ∼100 nm thick and exhibited a specular surface microstructure with a roughness of 0.31 nm RMS. The in-situ-deposited layer was thus employed as an intermediate layer prior to epitaxial layer growth using route (1) at ∼1450 °C. Regions free of one- and two-dimensional defects were observed using cross-sectional transmission electron microscopy. Distinct interfaces were not observed between the substrate and the epitaxial layers.}, number={1}, journal={JOURNAL OF CRYSTAL GROWTH}, author={Bishop, S. M. and Reynolds, C. L., Jr. and Liliental-Weber, Z. and Uprety, Y. and Ebert, C. W. and Stevie, F. A. and Park, J. -S. and Davis, R. F.}, year={2008}, month={Dec}, pages={72–78} }
 @article{bishop_park_gu_wagner_reltmeier_batchelor_zakharov_liliental-weber_davis_2007, title={Growth evolution and pendeo-epitaxy of non-polar AlN and GaN thin films on 4H-SiC (11(2)over-bar0)}, volume={300}, ISSN={["1873-5002"]}, DOI={10.1016/j.jcrysgro.2006.10.207}, abstractNote={The initial and subsequent stages of growth of AlN on 4H–SiC (1 1 2¯ 0) and GaN on AlN (1 1 2¯ 0) have been investigated using atomic force microscopy and X-ray photoelectron spectroscopy. The AlN nucleated and grew via the Stranski–Krastanov mode. Densely packed, [0 0 0 1]-oriented individual islands were observed at 10 nm. Additional deposition resulted in the gradual reorientation of the growth microstructure along the [1 1¯ 0 0]. GaN formed via the Volmer–Weber mode with rapid growth of islands along the [1 1¯ 0 0] to near surface coverage at a thickness of 2 nm. Continued deposition resulted in both faster vertical growth along [1 1 2¯ 0] relative to the lateral growth along [0 0 0 1] and a [1 1¯ 0 0]-oriented microstructure containing rows of GaN. Fully dense GaN films developed between 100 and 250 nm of growth, and the preferred in-plane orientation changed to [0 0 0 1]. Lateral growth of GaN films reduced the dislocation density from ∼4×1010 to ∼2×108 cm−2. The high concentration of stacking faults (∼106 cm−1) was also reduced two orders of magnitude.}, number={1}, journal={JOURNAL OF CRYSTAL GROWTH}, author={Bishop, S. M. and Park, J. -S. and Gu, J. and Wagner, B. P. and Reltmeier, Z. J. and Batchelor, D. A. and Zakharov, D. N. and Liliental-Weber, Z. and Davis, R. F.}, year={2007}, month={Mar}, pages={83–89} }
 @article{bishop_reynolds_liliental-weber_uprety_zhu_wang_park_molstad_barnhardt_shrivastava_et al._2007, title={Polytype stability and microstructural characterization of silicon carbide epitaxial films grown on [11(2)over bar0]- and [0001]-oriented silicon carbide substrates}, volume={36}, ISSN={["1543-186X"]}, DOI={10.1007/s11664-006-0076-2}, number={4}, journal={JOURNAL OF ELECTRONIC MATERIALS}, author={Bishop, S. M. and Reynolds, C. L., Jr. and Liliental-Weber, Z. and Uprety, Y. and Zhu, J. and Wang, D. and Park, M. and Molstad, J. C. and Barnhardt, D. E. and Shrivastava, A. and et al.}, year={2007}, month={Apr}, pages={285–296} }
 @article{park_fothergill_wellenius_bishop_muth_davis_2006, title={Origins of parasitic emissions from 353 nm AlGaN-based ultraviolet light emitting diodes over SiC substrates}, volume={45}, ISSN={["0021-4922"]}, DOI={10.1143/jjap.45.4083}, abstractNote={The effects of p-GaN capping layer and p-type carrier-blocking layer on the occurrence of parasitic emissions from 353 nm AlGaN-based light emitting diodes (LEDs) have been investigated. LEDs without a p-type Al0.25Ga0.75N carrier-blocking layer showed a shoulder peak at ∼370 nm due to electron overflow into the p-Al0.10Ga0.90N cladding layer and subsequent electron–hole recombination in the acceptor levels. Broad emission between 380 and 450 nm from LEDs having a p-GaN capping layer was caused by luminescence at 420 nm from the p-GaN capping layer, which was optically pumped by 353 nm UV emission from the quantum wells. Broad, defect-related luminescence centered at ∼520 nm was emitted from the AlGaN layers within the quantum wells.}, number={5A}, journal={JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS}, author={Park, JS and Fothergill, DW and Wellenius, P and Bishop, SM and Muth, JF and Davis, RF}, year={2006}, month={May}, pages={4083–4086} }
 @inbook{bishop_preble_hallin_henry_storasta_jacobson_wagner_reitmeier_janzen_davis_2004, title={Growth of homoepitaxial films on 4H-SiC(1120) and 8 degrees off-axis 4H-SiC(0001) substrates and their characterization}, volume={457-460}, booktitle={Silicon carbide and related materials 2003: ICSCRM2003: Proceedings of the 10th International Conference on Silicon Carbide and Related Materials 2003, Lyon, France, October 5-10, 2003}, publisher={Utikon-Zurich, Switzerland: Trans Tech Publications}, author={Bishop, S. M. and Preble, E. A. and Hallin, C. and Henry, A. and Storasta, L. and Jacobson, H. and Wagner, B. P. and Reitmeier, Z. and Janzen, E. and Davis, R. F.}, editor={R. Madar, J. Camassel and Blanquet, E.Editors}, year={2004}, pages={221–224} }