scholarly journals Experimental Evaluation of Bipolar Surface Potential with Corona Charging for Electret Activation

2020 ◽  
Vol 32 (7) ◽  
pp. 2493
Author(s):  
Koki Yamamoto ◽  
Takayuki Fujita ◽  
Adrien Badel ◽  
Fabien Formosa ◽  
Kensuke Kanda ◽  
...  
Keyword(s):  
Surface Potential ◽  
Experimental Evaluation ◽  
Corona Charging

scholarly journals Multilayer Inorganic Electrets with SiO2 and Si3N4 Layers for Applications on Heated Machinery

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Vladimir Leonov ◽  
Chris Van Hoof
Keyword(s):  
High Temperatures ◽  
Surface Potential ◽  
Elevated Temperatures ◽  
Single Layer ◽  
Lateral Mobility ◽  
Charge Retention ◽  
Basic Properties ◽  
Corona Charging ◽  
Trapped Charge

The physics and basic properties of electrets are discussed, namely, what happens during corona charging of dielectrics, why the surface potential and trapped charge show certain limits, where the trapped charge is stored, why and how the charge is released from traps at high temperatures. The experiments have been conducted on single-layer SiO2 and Si3N4 and on multilayer combination of these materials. A strong lateral mobility of charge trapped near the SiO2/Si3N4 interface was observed at elevated temperatures. The positively and negatively charged electrets are compared to each other. The experiments on charge retention at elevated temperatures have shown the studied electrets are suitable for devices working at temperatures of up to 200–300°C.

Accurate Doping Density Determination in SiC with Constant Surface Potential Corona Charging; Industry Ready Alternative to Hg-CV

2016 ◽  
Vol 858 ◽  
pp. 509-512 ◽  
Author(s):  
Alexander Savtchouk ◽  
Marshall Wilson ◽  
Jacek Lagowski ◽  
Andor Czett ◽  
Csaba Buday
Keyword(s):  
Surface Potential ◽  
Potential Method ◽  
Kelvin Probe ◽  
Doping Density ◽  
Density Determination ◽  
In Doping ◽  
Voltage Compensation ◽  
Corona Charging ◽  
Self Consistent ◽  
Improved Accuracy

We present a refined non-contact doping density determination in silicon carbide that incorporates 3 novel features: (1) constant surface potential method of corona charging into depletion; (2) vibrating Kelvin probe measurement of depletion surface voltage and voltage compensation maintaining constant surface potential, and (3) a unique self-consistent procedure for data analysis. The results obtained on epitaxial SiC demonstrate up to 3 times improved accuracy and enhanced repeatability giving 1σ in 10 repeats of 0.05% and 0.1% for doping in e15cm-3 and e19cm-3 range, respectively. An enhanced charging range enables measurement of high doping density in the e19cm-3 range and to achieve larger depth in doping profiling. With these refinements, a non-contact doping metrology for SiC represents an industry ready alternative to Hg-CV.

The effects of surface absorbed monolayer microdiffraction patterns

1988 ◽  
Vol 46 ◽  
pp. 680-681
Author(s):  
M. Pan ◽  
J.M. Cowley
Keyword(s):  
Surface Potential ◽  
Electron Probe ◽  
Potential Distribution ◽  
Crystal Surface ◽  
Normal Direction ◽  
Surface Image ◽  
Extended Surface ◽  
Gas Molecules ◽  
Surface Nature ◽  
Electron Microdiffraction

Electron microdiffraction patterns, obtained when a small electron probe with diameter of 10-15 Å is directed to run parallel to and outside a flat crystal surface, are sensitive to the surface nature of the crystals. Dynamical diffraction calculations have shown that most of the experimental observations for a flat (100) face of a MgO crystal, such as the streaking of the central spot in the surface normal direction and (100)-type forbidden reflections etc., could be explained satisfactorily by assuming a modified image potential field outside the crystal surface. However the origin of this extended surface potential remains uncertain. A theoretical analysis by Howie et al suggests that the surface image potential should have a form different from above-mentioned image potential and also be smaller by several orders of magnitude. Nevertheless the surface potential distribution may in practice be modified in various ways, such as by the adsorption of a monolayer of gas molecules.

Experimental Evaluation of the Dermoskeleton Concept: Addressing the Soldiers Overload Challenge

2012 ◽  
Author(s):  
Chris Ste-Croix ◽  
David Tack ◽  
Denis Boucher ◽  
Francois Ruel ◽  
Gilles Pageau ◽  
...  
Keyword(s):  
Experimental Evaluation
Sign in / Sign up

Export Citation Format

Share Document