The double barrier quantum well (DBQW) resonant tunneling diode (RTD) structure made of SiGeSn/GeC/SiGeSn alloys grown on Ge substrate is analyzed. The tensile strained Ge1-zCz on Si1-x-yGexSny heterostructure provides a direct band gap type I configuration. The transmission coefficient and tunneling current density have been calculated considering single and multiple quantum wells. A comparative study of tunnelling current of the proposed structure is done with the existing RTD structure based on GeSn/SiGeSn DBH. A higher value of the current density for the proposed structure has been obtained. © 2018 Chinese Institute of Electronics.

BRATATI MUKHOPADHYAY

Radio Physics and Electronics

S DEY

V CHAKRABORTY

G SEN

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Modeling of tunneling current density of GeC based double barrier multiple quantum well resonant tunneling diode

Journal of Semiconductors

Alloys of Ge and Sn grown on Si platform show about tenfold increase in the absorption over Ge at C and L-bands due to the direct nature of the band gap in GeSn. This led us to propose a Ge/GeSn/GeSn heterophototransistor (HPT) structure on a Si-platform and to calculate the terminal currents, current gain, optical gain and responsivity of the device at (Formula presented.). The model developed by Frimel and Roenker for HPTs with InGaAs base is used. In the model, the carrier density in the base is obtained by matching the diffusion-limited current with the current due to thermionic emission and tunneling across the emitter-base heterobarrier, and also considering the carrier density at the collector-end limited by the saturation drift velocity. The contribution of holes to the current is also included. The resulting carrier distribution is used to express the terminal currents and calculate the values of gain. The band gap for GeSn and the band discontinuity in the heterobarrier are calculated by using model solid theory. The calculated values for the GeSn HPT are found to be comparable with and even better than the corresponding values for the InP/InGaAs/InGaAs Npn device for lower values of the base thickness and the base doping. © 2014, Springer Science+Business Media New York.

Optical and Quantum Electronics

Predicted performance of Ge/GeSn hetero-phototransistors on Si substrate at 1.55Î¼m

The free carrier absorptions in strained Ge, relaxed GeSn and strained GeSn are estimated considering different scattering mechanisms, namely, acoustic phonon, non polar optical phonon and intervalley phonon scatterings. The change in absorption coefficient for different Sn concentration in the alloys is also reported. © 2012 IEEE.

CODEC 2012 - 5th International Conference on Computers and Devices for Communication

Free carrier absorption in Sn based Group-IV alloys

In this paper, we present our studies on current-voltage characteristics due to tunneling in nonuniform and asymmetric multiple quantum well (MQW) structures. First, the transmission coefficient is calculated by solving the Schrödinger equation with the piecewise-constant potential approximation and by considering the effects of nonuniformity and the asymmetry of layer dimensions and band-offsets. Then the tunneling current through the structure is calculated as a function of bias for different structural combinations of the MQW structure. The configurations suitable for some applications are indicated in the results. © 2011 American Institute of Physics.

Fulltext

Journal of Applied Physics

Tunneling current calculations for nonuniform and asymmetric multiple quantum well structures

We have calculated the composition of tensile strained Ge1-zCz on Ge1-x-y Six Sny heterostructures for which the indirect conduction band (L) lies above the zone centre (Γ) conduction band in the GeC layer in type I alignment. Linear interpolation of parameters indicates the possibility of achieving emission at 1.55 μm; however the direct gap shows a lower value when bowing parameters are considered. © 2010 Elsevier Ltd. All rights reserved.

Journal	Journal of Semiconductors
Publisher	Institute of Physics Publishing
ISSN	1674-4926
Open Access	No