Sub-micron InGaAs Esaki diodes with record high peak current density

The nanocrystalline nickel coating was synthesized by pulse-jet electrodeposition from modified Watts bath. Pulse and jet plating was employed to increase the deposition current density, decrease diffusion layer, increase the nucleation rate and in this case the prepared method would result in fine-grained deposits. Transmission and scanning electron microscopy and X-ray diffraction (XRD) were used to study the microstructure, the surface morphology, the crystal preferred orientation and the variety of the lattice parameter respectively. The influence of pulse parameters, namely peak current density, the duty cycle and pulse frequency on the grain size, surface morphology, crystal orientation and microstructure was studied. The results showed that with increasing peak current density, the deposit grain size was found to decrease markedly in other parameters at constant. However, in our experiment it was found that the grain size increased slightly with increasing pulse frequency. For higher peak current density, the surface morphology was smoother. The crystal orientation progressively changed from an almost random distribution to a strong (111) texture. This means that the peak current density was the dominated parameter to effect the microstructure of electrodeposited nanocrystalline nickel coating. In addition, the lattice parameter for the deposited nickel is calculated from XRD and it is found that the calculated value is less than the lattice parameter for the perfect nickel single crystal. This phenomenon is explained by the crystal lattice mismatch.

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Microstructure Evolution of As-Cast Nickel Aluminum Bronze under Electropulsing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.861.28 ◽

2020 ◽

Vol 861 ◽

pp. 28-34

Author(s):

Jie Fang ◽

Guo Lin Song ◽

Wei Liu ◽

Qiu Lin Li

Keyword(s):

Microstructure Evolution ◽

Current Density ◽

Phase Region ◽

Aluminum Bronze ◽

Nickel Aluminum ◽

Peak Current Density ◽

Peak Current ◽

Β Phase ◽

Nickel Aluminum Bronze ◽

Electropulsing Treatment

In this work, the microstructure evolution of as-cast NAB under different electropulsing parameters were studied. The microstructure of the electropulsing treatment (EPT) sample was characterized by mircohardness test and optical microscopy. The results show that compared with heat treatment, when the peak current density reaches 5.84×108A/m2 (no significant change in the structure when the peak current density is lower), the β' phase region undergo phase transition in a shorter time. When the peak current density reaches 7.25×108A/m2, the sample is significantly affected by the Joule heating effect, and the κⅢ and κⅣ phases are successively dissolved to form Widmanstätten α structure. As the β' phase increases and the Widmanstätten α structure forms, the hardness value of the microstructure increases by 80%.

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Benchmarking and improving III-V Esaki diode performance with a record 2.2 MA/cm2 peak current density to enhance TFET drive current

2012 International Electron Devices Meeting ◽

10.1109/iedm.2012.6479118 ◽

2012 ◽

Cited By ~ 11

Author(s):

D. Pawlik ◽

B. Romanczyk ◽

P. Thomas ◽

S. Rommel ◽

M. Edirisooriya ◽

...

Keyword(s):

Current Density ◽

Peak Current Density ◽

Drive Current ◽

Peak Current ◽

Esaki Diode

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