Annealing of Ion Implantation Damage in SiC Using a Graphite Mask

1999 ◽  
Vol 572 ◽  
Author(s):  
Chris Thomas ◽  
Crawford Taylor ◽  
James Griffin ◽  
William L. Rose ◽  
M. G. Spencer ◽  
...  
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Force Microscopy ◽  
Implantation Damage ◽  
Atomic Force ◽  
Capacitance Voltage ◽  
Implantation Process ◽  
Dopant Atoms ◽  
P Type ◽  
Secondary Ion ◽  
Ion Implanted

ABSTRACTFor p-type ion implanted SiC, temperatures in excess of 1600 °C are required to activate the dopant atoms and to reduce the crystal damage inherent in the implantation process. At these high temperatures, however, macrosteps (periodic welts) develop on the SiC surface. In this work, we investigate the use of a graphite mask as an anneal cap to eliminate the formation of macrosteps. N-type 4H- and 6H-SiC epilayers, both ion implanted with low energy (keV) Boron (B) schedules at 600 °C, and 6H-SiC substrates, ion implanted with Aluminum (Al), were annealed using a Graphite mask as a cap. The anneals were done at 1660 °C for 20 and 40 minutes. Atomic force microscopy (AFM), capacitance-voltage (C-V) and secondary ion mass spectrometry (SIMS) measurements were then taken to investigate the effects of the anneal on the surface morphology and the substitutional activation of the samples. It is shown that, by using the Graphite cap for the 1660 °C anneals, neither polytype developed macrosteps for any of the dopant elements or anneal times. The substitutional activation of Boron in 6H-SiC was about 15%.

Dielectric Properties of Thermally Grown SiO2 on 4H-SiC(0001) Substrates

2013 ◽  
Vol 740-742 ◽  
pp. 605-608 ◽  
Author(s):  
Takuji Hosoi ◽  
Yusuke Uenishi ◽  
Shuhei Mitani ◽  
Yuki Nakano ◽  
Takashi Nakamura ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Secondary Ion Mass Spectrometry ◽  
Oxide Thickness ◽  
Force Microscopy ◽  
Atomic Force ◽  
Capacitance Voltage ◽  
Linear Fit ◽  
Low Permittivity ◽  
Secondary Ion ◽  
Thermally Grown

The bulk properties of thermally grown SiO2 on 4H-SiC(0001) substrates were thoroughly investigated by capacitance-voltage (C-V) measurement, atomic force microscopy (AFM), spectroscopic ellipsometry (SE), x-ray photoelectron spectroscopy (XPS), and secondary ion mass spectrometry (SIMS). The equivalent oxide thickness (EOT) extracted from the capacitance-voltage (C-V) characteristics of TiN/SiO2 capacitors was proportional to the physical thickness (Tphys), but the slope of the linear fit was found to be 1.11, indicating that the permittivity of SiO2 on 4H-SiC formed by thermal oxidation is only about 3.5, which is lower than the commonly accepted value of 3.9. Since XPS analysis revealed that the oxide of SiC was stoichiometric and the atomic concentration of residual carbons in the oxide measured by SIMS was sufficiently low (1017 cm-3), the low permittivity of thermal oxides of 4H-SiC may originate from the reduced bulk density, which can be predicted by the Clausius-Mossotti relation.

Latest developments for microstructural and chemical characterization of diffusion bonding in superplastic 8090 Al–Li alloys

1996 ◽  
Vol 11 (1) ◽  
pp. 63-71 ◽  
Author(s):  
A. Ureña ◽  
J. M. Gómez de Salazar ◽  
J. J. Martín ◽  
J. Quiñones
Keyword(s):  
Surface Characterization ◽  
Secondary Ion Mass Spectrometry ◽  
Mixed Oxides ◽  
Chemical Characterization ◽  
Bond Line ◽  
Force Microscopy ◽  
Atomic Force ◽  
Bond Interface ◽  
Secondary Ion

This paper describes a new application of two complementary surface characterization techniques to study solid-state bonding in an Al–Li alloy. Through the two mentioned techniques, Atomic Force Microscopy (AFM) and Secondary Ion Mass Spectrometry (SIMS), important findings about what takes place in the bond interface have been determined. These findings enclose both the formation of discontinuous mixed oxides and the evolution of Li through the bond line and into theadjacent diffusion affected zones. Homogenization of Li and Cu alloyelements has been detected even in those cases where a metallic interlayer was used to favor the union.

ToF-SIMS Study of Polymer Nanocomposites.

2000 ◽  
Vol 661 ◽  
Author(s):  
Vladimir S. Zaitsev ◽  
Young-Soo Seo ◽  
Kwanwoo Shin ◽  
Wenhua Zhang ◽  
Steven A. Schwarz ◽  
...  
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
3D Structure ◽  
Three Dimensional ◽  
Correction Method ◽  
Force Microscopy ◽  
Atomic Force ◽  
Poly Ethylene ◽  
2D Data ◽  
Secondary Ion ◽  
Pmma Blends

ABSTRACTFilms of deuterated polystyrene (dPS) and poly(methyl methacrylate) (PMMA) blends, as well as dPS and PMMA and poly(ethylene-co-propylene) (PEP) blends have been spin-cast from toluene solution and annealed at temperatures above their glass transition temperatures for up to 72 hours. Surface topography of the cast and annealed films was measured by atomic force microscopy (AFM). Dynamic secondary ion mass spectrometry (SIMS) was used to study microphase segregation of the polymer films. A series of two-dimensional (2D) images of the films were acquired during sample sputtering. A reconstruction of the sample three-dimensional (3D) structure from 2D data was performed. Spatial distributions of H, D, C, O, and higher mass fragments revealed microphases with dimensions on the order of a few microns. We describe the method that corrects height distortion to 3D SIMS images. After sputtering, AFM is used to produce a topographic image of the area analyzed by SIMS. The surface height variation array from SIMS data was compared with that observed by AFM. A limitation of the correction method is discussed.

Windows into Microbial Seascapes: Advances in Nanoscale Imaging and Application to Marine Sciences

2019 ◽  
Vol 11 (1) ◽  
pp. 465-490 ◽  
Author(s):  
Gordon T. Taylor
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Spatial Scales ◽  
Niche Partitioning ◽  
Chemical Transformations ◽  
Force Microscopy ◽  
Atomic Force ◽  
Nanoscale Imaging ◽  
Confocal Raman Microspectroscopy ◽  
Phenotypic Variations ◽  
Secondary Ion

Geochemical cycles of all nonconservative elements are mediated by microorganisms over nanometer spatial scales. The pelagic seascape is known to possess microstructure imposed by heterogeneous distributions of particles, polymeric gels, biologically important chemicals, and microbes. While indispensable, most traditional oceanographic observational approaches overlook this heterogeneity and ignore subtleties, such as activity hot spots, symbioses, niche partitioning, and intrapopulation phenotypic variations, that can provide a deeper mechanistic understanding of planktonic ecosystem function. As part of the movement toward cultivation-independent tools in microbial oceanography, techniques to examine the ecophysiology of individual populations and their role in chemical transformations at spatial scales relevant to microorganisms have been developed. This review presents technologies that enable geochemical and microbiological interrogations at spatial scales ranging from 0.02 to a few hundred micrometers, particularly focusing on atomic force microscopy, nanoscale secondary ion mass spectrometry, and confocal Raman microspectroscopy and introducing promising approaches for future applications in marine sciences.

scholarly journals Synthesis and Growth of Gallium Nitride by the Chemical Vapor Reaction Process (CVRP)

1999 ◽  
Vol 4 (1) ◽  
Author(s):  
M. Callahan ◽  
M. Harris ◽  
M. Suscavage ◽  
D. Bliss ◽  
J. Bailey
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapor ◽  
Reaction Process ◽  
Seeded Growth ◽  
Bulk Crystal Growth ◽  
Force Microscopy ◽  
Resistivity Measurements ◽  
Atomic Force ◽  
New Process ◽  
Secondary Ion

A new process for synthesis and bulk crystal growth of GaN is described. GaN single crystal c-plane platelets up to 9mm by 2mm by 100μm thick have been grown by the Chemical Vapor Reaction Process (CVRP). The reaction between gallium and a nitrogen precursor is produced by sublimation of solid ammonium chloride in a carrier gas, which passes over gallium at a temperature of approximately 900°C at near atmospheric pressures. Growth rates for the platelets were 25-100 μm/hr in the hexagonal plane. Seeded growth in the c-direction was also accomplished by re-growth on previously grown c-plane platelets. The crystals were characterized by X-ray diffractometry, atomic force microscopy, secondary ion mass spectrometry, inert gas fusion, and room temperature Hall effect and resistivity measurements.

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