Effect of Varying Oxidation Parameters on the Generation of C-Dangling Bond Centers in Oxidized SiC

1999 ◽  
Vol 572 ◽  
Author(s):  
P. J. Macfarlane ◽  
M. E. Zvanut
Keyword(s):  
Heat Treatment ◽  
Field Effect Transistors ◽  
Wide Band ◽  
Hydrogen Release ◽  
Wide Band Gap ◽  
Paramagnetic Resonance ◽  
Dry Heat ◽  
Dry Heat Treatment ◽  
Oxidation Parameters ◽  
Mos Structures

ABSTRACTSiC is perhaps the most appropriate material to replace Si in power-metal-oxidesemiconductor- field-effect-transistors (MOSFETs), because, unlike the other wide band-gap semiconductors, SiC can be thermally oxidized similarly to Si to form a SiO2 insulating layer. In our studies of oxidized SiC, we have used electron paramagnetic resonance (EPR) to identify Cdangling bonds generated by hydrogen release from C-H bonds. While hydrogen's effect on SiCbased MOSFETs is uncertain, studies of Si-based MOSFETs indicate that it is important to minimize hydrogen in MOS structures. To examine the role of hydrogen, we have studied the effects of SiC/SiO2 fabrication on the density of C-related centers, which are made EPR active by a dry heat-treatment. Here we examine the starting and ending procedures of our oxidation routine. The parameter that appears to have the greatest effect on center density is the ending step of our oxidation procedure. For example, samples that were removed from the furnace in flowing O2 produced the smallest concentration of centers after dry heat-treatment. We report on the details of these experiments and use our results to suggest an oxidation procedure that limits center production.

EPR Study of the Role of Hydrogen in the Defect Formation Upon Heat Treatment of Oxidized SiC

1998 ◽  
Vol 513 ◽  
Author(s):  
P. J. Macfarlane ◽  
M. E. Zvanut
Keyword(s):  
Heat Treatment ◽  
Defect Formation ◽  
Wide Band ◽  
Oxide Semiconductor ◽  
Wide Band Gap ◽  
Paramagnetic Resonance ◽  
Hydrogen Incorporation ◽  
Si Substrates ◽  
Mos Devices ◽  
Dry Heat Treatment

ABSTRACTFor the past several years hydrogen incorporation in metal oxide semiconductor (MOS) devices has been of interest because studies have shown that vacuum annealing of oxidized Si substrates desorbs hydrogen, revealing interfacial defects. Today, in applications that require higher power and/or temperature, Si will likely be replaced with a wide-band-gap semiconductor. For MOS devices, SiC is a leading contender because it can be thermally oxidized to form a SiO2 insulating layer similar to Si. However, the SiC/SiO2 structure potentially contains hydrogen sensitive centers similar to those found in Si/SiO2 structures. Using electron paramagnetic resonance (EPR), we have observed a center 1.8 G wide peak-to-peak at g=2.0026. The center is generated in oxidized SiC that has received a 900° C dry, N2 or O2, post oxidation heat-treatment in which moisture is measured to be less than 1 ppm. Annealing at 900° C in standard Ar containing at least 50 ppm H2O decreases the center's concentration by two orders of magnitude. By comparing results from our study to studies of Si-H and C-H bonds in a-SiC:H [1] and SiC converted graphite [2], we suggest that this center is related to carbon dangling bonds created by the effusion of hydrogen during the dry heat-treatment. We will compare the activation energy for the hydrogen depassivation of our center with that found for other C-H and Si-H systems.

Kinetics of inactivating human parvovirus B19 and porcine parvovirus by dry-heat treatment

Transfusion ◽  
2008 ◽  
Vol 48 (4) ◽  
pp. 790-790 ◽  
Author(s):  
Johannes Blümel ◽  
Albert Stühler ◽  
Herbert Dichtelmüller
Keyword(s):  
Heat Treatment ◽  
Parvovirus B19 ◽  
Porcine Parvovirus ◽  
Human Parvovirus B19 ◽  
Dry Heat ◽  
Dry Heat Treatment ◽  
Kinetics Of

scholarly journals Effect of dry heat treatment along with some dormancy breaking chemicals on oil palm seed germination

2017 ◽  
Vol 112 ◽  
pp. 489-493
Author(s):  
K.M. Tabi ◽  
G.F. Ngando Ebongue ◽  
G.N. Ntsomboh ◽  
E. Youmbi
Keyword(s):  
Heat Treatment ◽  
Seed Germination ◽  
Oil Palm ◽  
Dormancy Breaking ◽  
Dry Heat ◽  
Dry Heat Treatment

scholarly journals Germination, Outgrowth, and Vegetative-Growth Kinetics of Dry-Heat-Treated Individual Spores ofBacillusSpecies

2018 ◽  
Vol 84 (7) ◽  
Author(s):  
Lin He ◽  
Zhan Chen ◽  
Shiwei Wang ◽  
Muying Wu ◽  
Peter Setlow ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Spore Germination ◽  
Differential Interference Contrast Microscopy ◽  
Content Type ◽  
Dry Heat ◽  
Heat Treated ◽  
Contrast Microscopy ◽  
Interference Contrast Microscopy ◽  
Dry Heat Treatment ◽  
Kinetics Of

ABSTRACTDNA damage kills dry-heated spores ofBacillus subtilis, but dry-heat-treatment effects on spore germination and outgrowth have not been studied. This is important, since if dry-heat-killed spores germinate and undergo outgrowth, toxic proteins could be synthesized. Here, Raman spectroscopy and differential interference contrast microscopy were used to study germination and outgrowth of individual dry-heat-treatedB. subtilisandBacillus megateriumspores. The major findings in this work were as follows: (i) spores dry-heat-treated at 140°C for 20 min lost nearly all viability but retained their Ca2+-dipicolinic acid (CaDPA) depot; (ii) in most cases, dry-heat treatment increased the average times and variability of all major germination events inB. subtilisspore germination with nutrient germinants or CaDPA, and in one nutrient germination event withB. megateriumspores; (iii)B. subtilisspore germination with dodecylamine, which activates the spore CaDPA release channel, was unaffected by dry-heat treatment; (iv) these results indicate that dry-heat treatment likely damages spore proteins important in nutrient germinant recognition and cortex peptidoglycan hydrolysis, but not CaDPA release itself; and (v) analysis of single spores incubated on nutrient-rich agar showed that while dry-heat-treated spores that are dead can complete germination, they cannot proceed into outgrowth and thus not to vegetative growth. The results of this study provide new information on the effects of dry heat on bacterial spores and indicate that dry-heat sterilization regimens should produce spores that cannot outgrow and thus cannot synthesize potentially dangerous proteins.IMPORTANCEMuch research has shown that high-temperature dry heat is a promising means for the inactivation of spores on medical devices and spacecraft decontamination. Dry heat is known to killBacillus subtilisspores by DNA damage. However, knowledge about the effects of dry-heat treatment on spore germination and outgrowth is limited, especially at the single spore level. In the current work, Raman spectroscopy and differential interference contrast microscopy were used to analyze CaDPA levels in and kinetics of nutrient- and non-nutrient germination of multiple individual dry-heat-treatedB. subtilisandBacillus megateriumspores that were largely dead. The outgrowth and subsequent cell division of these germinated but dead dry-heat-treated spores were also examined. The knowledge obtained in this study will help understand the effects of dry heat on spores both on Earth and in space, and indicates that dry heat can be safely used for sterilization purposes.

Effects of suppressing protein structural changes on the excellent gelling properties of dried egg white via dry-heat treatment

2021 ◽  
Vol 27 (2) ◽  
pp. 293-300
Author(s):  
Shota Koyama ◽  
Yuko Nemoto ◽  
Masahiro Ichikawa ◽  
Daiki Oka ◽  
Yoshimasa Tsujii ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Structural Changes ◽  
Egg White ◽  
Dry Heat ◽  
Gelling Properties ◽  
Dry Heat Treatment
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