Thermoelectric and Electrical Properties of Metal Intercalated Bilayer Graphene

2020 ◽  
Author(s):  
Jumpei Kihara ◽  
Yuki Okigawa ◽  
Masatou Ishihara ◽  
Setsuko Koura

Most thermoelectric materials that convert waste heat into electric power are inorganic materials, which poses problems in terms of flexibility and environmental load. Graphene is a carbon material with a two-dimensional structure and is expected to be a new thermoelectric material because it has peculiar electrical characteristics while having flexibility. In this study, as a result of investigating the thermoelectric properties of high-quality bilayer graphene synthesized by plasma CVD, the Seebeck coefficient was 70 μV/K and the power factor was 2,960 mW/mK^2. In addition, as a result of an experiment in which potassium was electrochemically intercalated into two-layer graphene, the Seebeck coefficient was improved, but the electrical conductivity was reduced. A slight negative shift of the Dirac point was seen in the measurement of electrical properties.

Author(s):  
F. M. Ross ◽  
R. Hull ◽  
D. Bahnck ◽  
J. C. Bean ◽  
L. J. Peticolas ◽  
...  

We describe an investigation of the electrical properties of interfacial dislocations in strained layer heterostructures. We have been measuring both the structural and electrical characteristics of strained layer p-n junction diodes simultaneously in a transmission electron microscope, enabling us to correlate changes in the electrical characteristics of a device with the formation of dislocations.The presence of dislocations within an electronic device is known to degrade the device performance. This degradation is of increasing significance in the design and processing of novel strained layer devices which may require layer thicknesses above the critical thickness (hc), where it is energetically favourable for the layers to relax by the formation of misfit dislocations at the strained interfaces. In order to quantify how device performance is affected when relaxation occurs we have therefore been investigating the electrical properties of dislocations at the p-n junction in Si/GeSi diodes.


Author(s):  
A.M. Letsoalo ◽  
M.E. Lee ◽  
E.O. de Neijs

Semiconductor devices require metal contacts for efficient collection of electrical charge. The physics of these metal/semiconductor contacts assumes perfect, abrupt and continuous interfaces between the layers. However, in practice these layers are neither continuous nor abrupt due to poor nucleation conditions and the formation of interfacial layers. The effects of layer thickness, deposition rate and substrate stoichiometry have been previously reported. In this work we will compare the effects of a single deposition technique and multiple depositions on the morphology of indium layers grown on (100) CdTe substrates. The electrical characteristics and specific resistivities of the indium contacts were measured, and their relationships with indium layer morphologies were established.Semi-insulating (100) CdTe samples were cut from Bridgman grown single crystal ingots. The surface of the as-cut slices were mechanically polished using 5μm, 3μm, 1μm and 0,25μm diamond abrasive respectively. This was followed by two minutes immersion in a 5% bromine-methanol solution.


Author(s):  
Woohui Lee ◽  
Changmin Lee ◽  
Jinyong Kim ◽  
Jehoon Lee ◽  
Deokjoon Eom ◽  
...  

To understand the effect of H2S pre-annealing treatment on a Si1-xGex alloy film, the interfacial and electrical characteristics of atomic-layer-deposited HfO2/Si1-xGex were studied while varying the Ge concentration (x value)...


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3154
Author(s):  
Kony Chatterjee ◽  
Tushar K. Ghosh

Since prehistoric times, textiles have served an important role–providing necessary protection and comfort. Recently, the rise of electronic textiles (e-textiles) as part of the larger efforts to develop smart textiles, has paved the way for enhancing textile functionalities including sensing, energy harvesting, and active heating and cooling. Recent attention has focused on the integration of thermoelectric (TE) functionalities into textiles—making fabrics capable of either converting body heating into electricity (Seebeck effect) or conversely using electricity to provide next-to-skin heating/cooling (Peltier effect). Various TE materials have been explored, classified broadly into (i) inorganic, (ii) organic, and (iii) hybrid organic-inorganic. TE figure-of-merit (ZT) is commonly used to correlate Seebeck coefficient, electrical and thermal conductivity. For textiles, it is important to think of appropriate materials not just in terms of ZT, but also whether they are flexible, conformable, and easily processable. Commercial TEs usually compromise rigid, sometimes toxic, inorganic materials such as bismuth and lead. For textiles, organic and hybrid TE materials are more appropriate. Carbon-based TE materials have been especially attractive since graphene and carbon nanotubes have excellent transport properties with easy modifications to create TE materials with high ZT and textile compatibility. This review focuses on flexible TE materials and their integration into textiles.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Pei-Ju Chao ◽  
Eng-Yen Huang ◽  
Kuo-Sheng Cheng ◽  
Yu-Jie Huang

Electrical impedance is one of the most frequently used parameters for characterizing material properties. The resistive and capacitive characteristics of tissue may be revealed by electrical impedance spectroscopy (EIS) as electrical biopsy. This technique could be used to monitor the sequelae after irradiation. In this study, rat intestinal tissues after irradiation were assessed by EIS system based on commercially available integrated circuits. The EIS results were fitted to a resistor-capacitor circuit model to determine the electrical properties of the tissue. The variations in the electrical characteristics of the tissue were compared to radiation injury score (RIS) by morphological and histological findings. The electrical properties, based on receiver operation curve (ROC) analysis, strongly reflected the histological changes with excellent diagnosis performance. The results of this study suggest that electrical biopsy reflects histological changes after irradiation. This approach may significantly augment the evaluation of tissue after irradiation. It could provide rapid results for decision making in monitoring radiation sequelae prospectively.


1980 ◽  
Vol 86 (1) ◽  
pp. 49-61
Author(s):  
G. F. GWILLIAM ◽  
M. BURROWS

1. The electrical properties of the membrane of an identified locust motor neurone, the fast extensor tibiae in the metathoracic ganglion, have been investigated to determine: the distribution of excitable and inexcitable membrane; the impulse initiation zone; and the conduction velocity of the spike in the ganglion and in the axon. 2. The waveform of extracellularly recorded spikes indicates that the transition from inactive to active membrane occurs along the region of the neurite which bears many arborizations within the neuropile. 3. Measurements of the delay between orthodromically or antidromically evoked spikes, recorded at the soma and other points along the neurite, place the impulse initiating zone close to the transition between active and inactive membrane. 4. Within the ganglion, the spike is conducted at different velocities over different parts of the neurite. The average velocity within the ganglion is, however, only about a seventh of that in the axon (0.54 m.s−1 against 4.1 m.s−1).


1979 ◽  
Vol 78 (1) ◽  
pp. 201-211
Author(s):  
C. K. LANGLEY

(1) Thermal acclimation of the Fi neurone does not appear to result from changes in the chemical composition of the haemolymph. This is deduced from the lack of effect on the electrical characteristics of control neurones of either pooled haemolymph from acclimated individuals, or variations in the experimental salines made in accordance with haemolymph analyses. (2) Changes in [Ca]0 tended to act cooperatively with temperature shifts to induce alterations in the electrical properties of the neurone, notably to increase excitability and lower membrane resistance. (3) Warm acclimation was associated with increased resting conductance of the neuronal membrane to sodium and potassium, whereas chloride conductance appeared little affected.


1982 ◽  
Vol 13 ◽  
Author(s):  
B-Y. Tsaur ◽  
John C. C. Fan ◽  
M. W. Geis ◽  
R. L. Chapman ◽  
S. R. J. Brueck ◽  
...  

ABSTRACTDevice-quality Si films have been prepared by using graphite strip heaters for zone melting poly-Si films deposited on SiO2-coated substrates. The electrical characteristics of these films have been studied by the fabrication and evaluation of thin-film resistors, Mosfets and MOS capacitors. High yields of functional transistor arrays and ring oscillators with promising speed performance have been obtained for CMOS test circuit chips fabricated in recrystallized Si films on 2-inch-diameter Si wafers. Dualgate Mosfets with a three-dimensional structure have been fabricated by using the zone-melting recrystallization technique.


1981 ◽  
Vol 4 ◽  
Author(s):  
G. Auvert ◽  
D. Bensahel ◽  
A. Perio ◽  
F. Morin ◽  
G.A. Rozgonyi ◽  
...  

ABSTRACTExplosive Crystallization occurs in cw laser annealing on a-Si films deposited on glass substrates at laser scan speeds higher than 30 cm/sec. Optical, structural and electrical properties of the crystallized films at various laser scan speeds confirm the existence of two kinds of explosive growth depending on the state of crystallinity of the starting material.


Sign in / Sign up

Export Citation Format

Share Document