scholarly journals Importance of Interfacial Structures in the Catalytic Effect of Transition Metals on Diamond Growth

ACS Omega ◽  
2021 ◽  
Author(s):  
Jeong Woo Yang ◽  
Jong Hwan Park ◽  
Min Gyo Byun ◽  
Nong Moon Hwang ◽  
Jinwoo Park ◽  
...  
Keyword(s):  
Transition Metals ◽  
Catalytic Effect ◽  
Diamond Growth ◽  
Interfacial Structures

The Origin of Mis-Oriented Diamond Grains Nucleated Directly on (001) Silicon Surface

1998 ◽  
Vol 529 ◽  
Author(s):  
R.Q. Zhang ◽  
W.J. Zhang ◽  
C. Sun ◽  
X. Jiang ◽  
S.-T. Lee
Keyword(s):  
Grain Orientation ◽  
Silicon Surface ◽  
Diamond Films ◽  
Orientation Distribution ◽  
Interface Structure ◽  
Silicon Surfaces ◽  
Diamond Growth ◽  
Diamond Nucleation ◽  
Interfacial Structures ◽  
Zero Degree

AbstractThe origin of mis-oriented diamond grains frequently observed in heteroepitaxial diamond films on (001) silicon surfaces was studied. By statistically analyzing the in-plane rotation angles of diamond grains in scanning electron microscopy observations, it was found that the distribution of the grain orientation is not random and two satellite distribution peaks at about 20° and 30° accompany the main distribution peak at zero degree referenced to the <110> direction of substrate. The interface structure corresponding to the main distribution peak at zero degree of oriented diamond growth has been proposed in our previous studies. In this study, our molecular orbital PM3 simulation of a step-by-step diamond nucleation further reveals two other metastable diamond/silicon interfacial structures. The orientations of the corresponding diamond grains are parallel to the (001) silicon surface but with in-plane rotations of 20° and 30° respectively with respect to the <110> direction. We relate these two mis-oriented growths to the two satellite peaks of grain orientation distribution. Based on this study, the possibility in experiment to reduce the formation of mis-oriented configurations and to obtain a perfectly oriented diamond growth is discussed.

Neue Synthesen von Magnesiumhydrid / New Syntheses of Magnesium Hydride

1992 ◽  
Vol 47 (6) ◽  
pp. 767-771 ◽  
Author(s):  
Götz Koerner ◽  
Klaus-Dieter Klein ◽  
Wilfried Knott
Keyword(s):  
Transition Metals ◽  
Catalytic Effect ◽  
Hydrogen Uptake ◽  
Magnesium Hydride ◽  
Kinetics Of

A very easy and safe way for the production of Ni-doped magnesium hydride is reported. Another process, which is not requiring transition metals (e. g. nickel) has also been found as a means to ameliorate the kinetics of hydrogen uptake. MgH2 itself exerts a catalytic effect on the formation of magnesium hydride from the elements, i. e. by autocatalysis.

DNA-Based Biosensor for Comparative Study of Catalytic Effect of Transition Metals on Autoxidation of Sulfite

2012 ◽  
Vol 85 (2) ◽  
pp. 991-997 ◽  
Author(s):  
Ali A. Ensafi ◽  
Esmaeil Heydari-Bafrooei ◽  
Behzad Rezaei
Keyword(s):  
Transition Metals ◽  
Comparative Study ◽  
Catalytic Effect

Precipitation in silicon: Microanalysis

1988 ◽  
Vol 46 ◽  
pp. 474-475
Author(s):  
R.W. Carpenter
Keyword(s):  
Transition Metals ◽  
Spatial Resolution ◽  
Thin Foil ◽  
Precipitation Reaction ◽  
High Current ◽  
Reaction Products ◽  
Carbon And Nitrogen ◽  
Dielectric Layers ◽  
Precipitation Processes ◽  
Areas Of Interest

Interest in precipitation processes in silicon appears to be centered on transition metals (for intrinsic and extrinsic gettering), and oxygen and carbon in thermally aged materials, and on oxygen, carbon, and nitrogen in ion implanted materials to form buried dielectric layers. A steadily increasing number of applications of microanalysis to these problems are appearing. but still far less than the number of imaging/diffraction investigations. Microanalysis applications appear to be paced by instrumentation development. The precipitation reaction products are small and the presence of carbon is often an important consideration. Small high current probes are important and cryogenic specimen holders are required for consistent suppression of contamination buildup on specimen areas of interest. Focussed probes useful for microanalysis should be in the range of 0.1 to 1nA, and estimates of spatial resolution to be expected for thin foil specimens can be made from the curves shown in Fig. 1.

The value of Electron Microscope studies of imperfect natural diamonds

1990 ◽  
Vol 48 (4) ◽  
pp. 194-195
Author(s):  
J C Walmsley ◽  
A R Lang
Keyword(s):  
Electron Microscope ◽  
Classification Scheme ◽  
Natural Diamond ◽  
Sudden Change ◽  
Growth Conditions ◽  
Diamond Growth ◽  
Major Constituent ◽  
Natural Diamonds ◽  
Type Ia ◽  
Platelet Defects

Interest in the defects and impurities in natural diamond, which are found in even the most perfect stone, is driven by the fact that diamond growth occurs at a depth of over 120Km. They display characteristics associated with their origin and their journey through the mantle to the surface of the Earth. An optical classification scheme for diamond exists based largely on the presence and segregation of nitrogen. For example type Ia, which includes 98% of all natural diamonds, contain nitrogen aggregated into small non-paramagnetic clusters and usually contain sub-micrometre platelet defects on {100} planes. Numerous transmission electron microscope (TEM) studies of these platelets and associated features have been made e.g. . Some diamonds, however, contain imperfections and impurities that place them outside this main classification scheme. Two such types are described.First, coated-diamonds which possess gem quality cores enclosed by a rind that is rich in submicrometre sized mineral inclusions. The transition from core to coat is quite sharp indicating a sudden change in growth conditions, Figure 1. As part of a TEM study of the inclusions apatite has been identified as a major constituent of the impurity present in many inclusion cavities, Figure 2.

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