Indian Institute of Technology Palakkad&nbsp;(IIT Palakkad or IIT PKD) is a public autonomous&nbsp;engineering&nbsp;and&nbsp;research&nbsp;institute located in&nbsp;Palakkad,&nbsp;Kerala. It was&nbsp;one of the five new&nbsp;IITs&nbsp;proposed in the&nbsp;2014 Union budget of India. The campus was inaugurated on 3 August 2015. The institute has 94 faculty, 978 students, and 63 non-teaching staffs.

IT Palakkad currently offers four-year Bachelor of Technology (B.Tech) and two years MS programmes in 8 different engineering disciplines including&nbsp;Computer Science, Electrical, Mechanical, Civil among others.

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IIT Palakkad

As semiconductor devices scale to new dimensions, the materials and designs become more dependent on atomic details. NEMO5 is a nanoelectronics modeling package designed for comprehending the critical multi-scale, multi-physics phenomena through efficient computational approaches and quantitatively modeling new generations of nanoelectronic devices as well as predicting novel device architectures and phenomena. This article seeks to provide updates on the current status of the tool and new functionality, including advances in quantum transport simulations and with materials such as metals, topological insulators, and piezoelectrics. © 2013 Springer Science+Business Media New York.

World University root node

Department of Electrical Engineering

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Journal of Computational Electronics

Efficient and realistic device modeling from atomic detail to the nanoscale

Complex bands k(E) in a semiconductor crystal, along a general direction n, can be computed by casting Schrödingers equation as a generalized polynomial eigenvalue problem. When working with primitive lattice vectors, the order of this eigenvalue problem can grow large for arbitrary n. It is, however, possible to always choose a set of non-primitive lattice vectors such that the eigenvalue problem is restricted to be quadratic. The complex bands so obtained need to be unfolded onto the primitive Brillouin zone. In this paper, we present a unified method to unfold real and complex bands. Our method ensures that the measure associated with the projections of the non-primary wavefunction onto all candidate primary wavefunctions is invariant with respect to the energy E. © 2012 IOP Publishing Ltd.

Journal of Physics Condensed Matter

Brillouin zone unfolding of complex bands in a nearest neighbour tight binding scheme

Band to band tunneling in semiconductors fundamentally depends of the complex bandstructure of the semiconductor within its bandgap. In this work, the orientation dependent complex bandstructure of InSb, InAs, GaSb, InP and GaAs, and the orientation dependent probability of band to band tunneling in these materials have been computed using an sp3d5s* tight binding model. These direct bandgap III-V materials are attractive candidates for Tunnel FETs. Comparison of our results with Kane's two-band model commonly used in TCAD simulation, demonstrates the inaccuracies of the latter. Our results will be useful in the design of better performing Tunnel FETs in these materials. © 2012 SPIE.

Proceedings of SPIE - The International Society for Optical Engineering

Complex bandstructure of direct bandgap III-V semiconductors: Application to tunneling

In this work, we study the phenomenon of Direct Tunneling(DT) in Metal-nGaN Schottky junctions. We first compare tunneling current densities computed using quantum (NEGF) and the semi-classical (WKB) transport formulations, based on a single band parabolic approximation to the complex GaN bandstructure. We then estimate current densities using the WKB transport formulation, with complex bandstructures extracted from the two band k·p and four band k·p theories of the wurtzite GaN. We find that a WKB transport formulation is quite reliable for low bias values. We also find that the use of multi-band k·p models for calculating tunneling effective mass is necessary to estimate tunneling current densities accurately. © 2012 IEEE.

2012 International Conference on Emerging Electronics, ICEE 2012

Comparison of direct tunneling in Metal-GaN Schottky junctions using different k·p models for the complex bandstructure

Band-to-band tunneling (BTBT) determines the on-current in tunnel FETs (TFETs). There is a need to review and recalibrate BTBT models used in TCAD tools, which were developed when BTBT was essentially a leakage phenomenon. Here, we consider the process of BTBT through staggered heterojunctions which find application in the design of TFETs having high on-currents. We use a simple 1-D system and compare the estimates of BTBT computed with a semi-classical WKB approach and that obtained from a solution of Schrödinger's equation by a wavefunction matching procedure. We show that the WKB method significantly overestimates the tunneling current through heterojunctions. © 2012 IEEE.

2012 15th International Workshop on Computational Electronics, IWCE 2012

Band to band tunneling in heterojunctions: Semi-classical versus quantum computation

Over the last decade, Si1-xGex has increasingly been used as a channel material in MOSFETs. Though many studies have dealt with the real bandstructure of Si1-xGex, the effect of germanium mole fraction x on complex bandstructure has been unexplored. Complex bands fundamentally determine band to band tunneling (BTBT) current. For example, using the orientation dependent complex bandstructure of silicon [1], it has been shown [2] that the BTBT current in the [110] direction is an order of magnitude larger than that along the [100] direction. BTBT contributes significantly to off-current Ioff in conventional MOSFETs, via the mechanism of gate induced drain leakage (GIDL). Additionally, BTBT determines the on current Ion in tunneling FETs, which have been suggested as next generation devices. Further, BTBT is more dominant in Si 1-xGex than silicon, owing to a narrower bandgap. In this work, we determine the orientation dependent complex bandstructure of Si 1-xGex along common crystallographic directions and predict trends in BTBT current. © 2011 IEEE.

Device Research Conference - Conference Digest, DRC

Orientation dependent complex bandstructure of Si1-xGe x alloys

Computing the electronic energy levels of a finite system or nanostructure is more difficult than computing those of an infinite system or bulk material. In the literature, a technique for simplifying this computation has been proposed, wherein energy levels of a finite system are derived from those of the corresponding infinite system. So far, this method has been validated only for finite length one-dimensional systems and for higher-dimensional systems at k = 0. We establish that this technique, hereafter referred to as the confined Bloch wave (CBW) method, is valid for higher-dimensional symmorphic systems over the entire Brillouin zone, provided some symmetry requirements are satisfied. For this purpose we use a lateral surface superlattice as a model for the infinite system and a stripe or ribbon patterned in this superlattice as a model for the nanostructure. Finally, we compute the subbands of zigzag ribbons of one type patterned in artificial graphene and show that the CBW method predicts all the important subbands in these ribbons, and provides additional insight into the nature of their wavefunctions. © 2010 IOP Publishing Ltd.