Observation of the Surface Morphology on the (0001)C Facet of 4H-SiC Boules

2015 ◽  
Vol 821-823 ◽  
pp. 64-67
Author(s):  
Tomoki Yamaguchi ◽  
Shunsuke Sato ◽  
Noboru Ohtani ◽  
Masakazu Katsuno ◽  
Tatsuo Fujimoto ◽  
...  

The surface morphology on the (000-1)C facet of 4H-SiC boules grown by the physical vapor transport method was examined in various scales (from millimeter to nanometer) using different types of microscopies such as differential interference contrast (DIC) optical microscopy and atomic force microscopy (AFM). The DIC optical microscope observation revealed that there exist three distinct morphological regions at the growth front of the 4H-SiC boules; they are facetted, non-facetted, and the intermediate region between them. The local inclination of the facet surface from the (000-1) basal plane increases toward the facet edge and then decreases over the intermediate region. AFM observations revealed characteristic step structures in these two regions and also that they are significantly influenced by nitrogen-doping. Based on the results, the formation mechanism of the facet morphology on 4H-SiC boules is discussed.

2017 ◽  
Vol 68 (11) ◽  
pp. 2700-2703 ◽  
Author(s):  
Kamel Earar ◽  
Vasile Iulian Antoniac ◽  
Sorana Baciu ◽  
Simion Bran ◽  
Florin Onisor ◽  
...  

This study examined and compared surface of human dentine after acidic etching with hydrogen peroxide, phosphoric acid liquid and gel. Surface demineralization of dentin is necessary for a strong bond of adhesive at dental surface. Split human teeth were used. After application of mentioned substances at dentin level measures of the contact angle and surface morphology were employed. Surface morphology was analyzed with the help of scanning electron microscopy and atomic force microscopy. Liquid phosphoric acid yielded highest demineralization showing better hydrophobicity than the rest, thus having more contact surface. Surface roughness are less evident and formed surface micropores of 4 �m remained open after wash and air dry providing better adhesive canalicular penetration and subsequent bond.


1992 ◽  
Author(s):  
Mark R. Kozlowski ◽  
Michael C. Staggs ◽  
Mehdi Balooch ◽  
Robert J. Tench ◽  
Wigbert J. Siekhaus

1999 ◽  
Vol 200 (3-4) ◽  
pp. 348-352 ◽  
Author(s):  
R.S Qhalid Fareed ◽  
S Tottori ◽  
K Nishino ◽  
S Sakai

2016 ◽  
Vol 857 ◽  
pp. 79-82
Author(s):  
Roslina Ismail ◽  
Fuaida Harun ◽  
Azman Jalar ◽  
Shahrum Abdullah

This work is a contribution towards the understanding of wire bond integrity and reliability in relation to their microstructural and mechanical properties in semiconductor packaging.The effect of surface roughness and hardness of leadframe on the bondability of Au wedge bond still requires detail analysis. Two type of leadframes namely leadframe A and leadframe B were chosen and scanning electron microscope (SEM) and optical microscope were used to inspect the surface morphology of leadframes and the quality of created Au wedge bond after wire bonding process. It was found that there were significant differences in the surface morphologies between these two leadframes. The atomic force microscopy (AFM) which was utilized to measure the average roughness, Ra of lead finger confirms that leadframe A has the highest Ra with value of 166.46 nm compared to that of leadframe B with value of 85.89 nm. While hardness value of different lead finger from the selected leadframe A and B obtained using Vicker microhardness tester are 180.9 VH and 154.2VH respectively.


2021 ◽  
Vol 314 ◽  
pp. 302-306
Author(s):  
Quoc Toan Le ◽  
E. Kesters ◽  
M. Doms ◽  
Efrain Altamirano Sánchez

Different types of ALD Ru films, including as-deposited, annealed Ru, without and with a subsequent CMP step, were used for wet etching study. With respect to the as-deposited Ru, the etching rate of the annealed Ru film in metal-free chemical mixtures (pH = 7-9) was found to decrease substantially. X-ray photoelectron spectroscopy characterization indicated that this behavior could be explained by the presence of the formation of RuOx (x = 2,3) caused by the anneal. A short CMP step applied to the annealed Ru wafer removed the surface RuOx, at least partially, resulting in a significant increase of the etching rate. The change in surface roughness was quantified using atomic force microscopy.


1999 ◽  
Vol 594 ◽  
Author(s):  
M. E. Ware ◽  
R. J. Nemanich

AbstractThis study explores stress relaxation of epitaxial SiGe layers grown on Si substrates with unique orientations. The crystallographic orientations of the Si substrates used were off-axis from the (001) plane towards the (111) plane by angles, θ = 0, 10, and 22 degrees. We have grown 100nm thick Si(1−x) Ge(x) epitaxial layers with x=0.3 on the Si substrates to examine the relaxation process. The as-deposited films are metastable to the formation of strain relaxing misfit dislocations, and thermal annealing is used to obtain highly relaxed films for comparison. Raman spectroscopy has been used to measure the strain relaxation, and atomic force microscopy has been used to explore the development of surface morphology. The Raman scattering indicated that the strain in the as-deposited films is dependent on the substrate orientation with strained layers grown on Si with 0 and 22 degree orientations while highly relaxed films were grown on the 10 degree substrate. The surface morphology also differed for the substrate orientations. The 10 degree surface is relatively smooth with hut shaped structures oriented at predicted angles relative to the step edges.


1995 ◽  
Vol 413 ◽  
Author(s):  
V. Shivshankar ◽  
C. Sung ◽  
J. Kumar ◽  
S. K. Tripathy ◽  
D. J. Sandman

ABSTRACTWe have studied the surface morphology of free standing single crystals of thermochromic polydiacetylenes (PDAs), namely, ETCD and IPUDO (respectively, the ethyl and isopropyl urethanes of 5,7-dodecadiyn-1,12-diol), by Atomic Force Microscopy (AFM) under ambient conditions. Micron scale as well as molecularly resolved images were obtained. The micron scale images indicate a variable surface, and the molecularly resolved images show a well defined 2-D lattice that is interpreted in terms of molecular models and known crystallographic data. Thereby information about surface morphology, which is crucial to potential optical device or chromic sensor performance is available. We also report the observation of a “macroscopic shattering” of the IPUDO monomer crystal during in-situ UV polymerization studies.


Author(s):  
Mikhail Ihnatouski ◽  
Dmitriy Karev ◽  
Boris Karev ◽  
Jolanta Pauk ◽  
Kristina Daunoravičienė

Introduction: Osteoarthritis is a chronic, progressive disease. The aim of this paper is presenting the AFM investigation of cartilage in relation to the assessment of degenerative changes in the surface of hyaline cartilage. It can be useful in choosing the most effective methods of therapy. Methods: Samples were taken from the cartilage surface of the femoral head after its removal during total hip arthroplasty. Images of the surface of the sample were obtained using an optical microscope equipped with a digital video camera, in the reflected light and by atomic force microscopy. Results: The longitudinal orientation of the collagen fibers and sub-fibers beams on the surface, up to a diameter of 50 nm are identified in non-destroyed area sites. Conclusions: Images of the destroyed areas displaying separately passing collagen fibers, strongly exposed to the surface: the size measured and found substructure.


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