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Hafizur Rahaman

Other affiliations: Khulna University, Yahoo!, Assam University  ...read more
Bio: Hafizur Rahaman is an academic researcher from Indian Institute of Engineering Science and Technology, Shibpur. The author has contributed to research in topics: Biochip & Logic gate. The author has an hindex of 21, co-authored 471 publications receiving 2766 citations. Previous affiliations of Hafizur Rahaman include Khulna University & Yahoo!.


Papers
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Journal ArticleDOI
TL;DR: In this article, a short-gate tunneling-field-effect-transistor (SG-TFET) structure has been investigated for the dielectrically modulated biosensing applications in comparison with a full-gate TFET structure of similar dimensions.
Abstract: In this paper, a short-gate tunneling-field-effect-transistor (SG-TFET) structure has been investigated for the dielectrically modulated biosensing applications in comparison with a full-gate tunneling-field-effect-transistor structure of similar dimensions. This paper explores the underlying physics of these architectures and estimates their comparative sensing performance. The sensing performance has been evaluated for both the charged and charge-neutral biomolecules using extensive device-level simulation, and the effects of the biomolecule dielectric constant and charge density are also studied. In SG-TFET architecture, the reduction of the gate length enhances its drain control over the band-to-band tunneling process and this has been exploited for the detection, resulting to superior drain current sensitivity for biomolecule conjugation. The gate and drain biasing conditions show dominant impact on the sensitivity enhancement in the short-gate biosensors. Therefore, the gate and drain bias are identified as the effective design parameters for the efficiency optimization.

141 citations

Journal ArticleDOI
TL;DR: In this article, the effect of use of silicon-germanium (SiGe) source and n+-pocket-doped channel is investigated with the help of extensive device-level simulations.
Abstract: Dielectrically modulated tunnel FET (DMTFET)-based biosensors show higher sensitivity but lower subthreshold current compared with their dielectrically modulated FET counterpart. In this context, the effect of use of silicon–germanium (SiGe) source and n+-pocket-doped channel is investigated with the help of extensive device-level simulations. This paper explores the underlying physics of germanium composition variation in the source region, and doping concentration variation in n+-pocket region, from the perspective of biomolecule conjugation. The effects of source bandgap and tunneling length over the band-to-band tunneling component have been analyzed, and, subsequently, the sensing performance of DMTFETs has been estimated. The results show that SiGe-source DMTFET has significant superiority over n+-pocket DMTFET for attaining higher subthreshold current level while retaining acceptable sensitivity. Such sensitivity-current optimization has been studied for different gate and drain biases, and the suitable biasing range of operation has been indicated. In addition, the relative efficiency of SiGe source and n+-pocket-doped channel has been studied under different biomolecule sample specifications. Finally, the influence of trap-assisted tunneling on DMTFET sensing performance has been analyzed, and the comparative role of SiGe source and n+ pocket has also been indicated in this context.

123 citations

Journal ArticleDOI
TL;DR: In this paper, the impact of crosstalk effects in carbon nanotube (CNT) interconnects and its impact on the gate oxide reliability was analyzed and the results showed that the CNT-based interconnect is more suitable in VLSI circuits as far as the gate oxidation is concerned.
Abstract: This paper analyses the crosstalk effects in carbon nanotube (CNT) interconnect, and its impact on the gate oxide reliability. Using the existing models of CNT, circuit parameters for the single-wall CNT-bundle and multiwall CNT interconnects are calculated and the equivalent circuit has been developed to perform the crosstalk analysis. The crosstalk-induced overshoot/undershoots have been estimated and the impact of the overshoot/undershoots on the gate oxide reliability in terms of failure-in-time rate is calculated. A similar analysis is performed for Cu-based interconnects and comparisons are made with the results obtained for CNT-based interconnect. It has been found that the CNT-based interconnect is more suitable in VLSI circuits as far as the gate oxide reliability is concerned.

74 citations

Journal ArticleDOI
TL;DR: The proposed EFDR technique is capable of detecting and managing the faulty nodes in an efficient manner and the simulation results show 86% improvement in the rate of energy loss compared to an existing algorithm.

62 citations

Journal ArticleDOI
TL;DR: A collection of open access and proprietary software and services are identified and combined via a practical workflow which can be used for 3D reconstruction to MxR visualisation of cultural heritage assets.

59 citations


Cited by
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TL;DR: The Beloit College Mindset List provides a look at the cultural background of the students entering college that fall, and what's the worldview of the class of 2014?
Abstract: 'When I was your age,' my father was fond of telling me, 'I used to walk 5 miles through a foot of snow just to go to school.' I was impressed for a while, until I noticed that, as he got older, the distance got longer and the snow got deeper. Eventually, he claimed to have walked 20 miles through 6 feet of snow. I became even more suspicious when I found out from my grandmother that they had lived three blocks from school. In an age of school buses and car-pooling parents, such stories, whether believable or not, conjure up visions of a world almost beyond the imaginations of today's children. I was reminded of that today by an email from my friend and Brandeis colleague Tom Pochapsky, who directed my attention to a fascinating article on the website of Beloit College (http://www.beloit.edu/mindset/2014.php). Each August since 1998, Beloit College has released the Beloit College Mindset List, which provides a look at the cultural background of the students entering college that fall. The creation of Beloit's Keefer Professor of the Humanities Tom McBride and former Public Affairs Director Ron Nief, it was originally created as a reminder to the Beloit faculty to be aware of dated references. As the website notes, 'it quickly became a catalog of the rapidly changing worldview of each new generation.' So what's the worldview of the class of 2014? According to the latest list, here are a few of the things these 18-year-olds, born in 1992, have experienced - and not experienced: • Few in the class know how to write in cursive. • They find that email is just too slow, and they seldom if ever use snail mail. They text. Oh, God, do they text. • To them, Clint Eastwood is better known as a sensitive film director than as vigilante cop Dirty Harry. • For them, Korean cars have always been a staple on American highways. • They've never recognized that pointing to their wrists was a request for the time of day. • In their world, Czechoslovakia has never existed. There was no Berlin Wall, the Iron Curtain is a meaningless phrase, and Russia has never had a Communist government. • There has never been a world without AIDS. • The Beatles and the Rolling Stones are classical music. • Toothpaste tubes have always stood up on their caps. • There have always been women priests in the Anglican Church. • Having hundreds of cable channels but nothing good to watch has always been the norm. • The US public has never approved of the job the US Congress is doing. • Most of them have never seen a long-playing record, or even a tape drive. If they have ever seen a typewriter, it was in a museum, possibly alongside a dial telephone. • They have never lived in a world without personal computers, the Internet, CD-ROMs or laser printers. There are, of course, many things they have experienced that we also experienced at the same age. Among these are automobiles, jet airplanes, color television sets, and the Chicago Cubs not having won the World Series. Another commonality has been the enduring hostility between the English and the French. But they couldn't imagine life without PopTarts, juice boxes, and movies you can have on your home TV, and they have no idea how we could have survived in a world that required carbon paper. All of which got me wondering: what would the scientific worldview be like for someone, let's say, just starting graduate school today (and therefore about 22 years of age)? Born in 1988, how would their scientific lives differ from the lives of the generations preceding them (including mine, which is the only one I really care about)? It makes for some interesting speculation: • For today's budding biologists, DNA fingerprinting would have always existed. Actual fingerprinting would have been a recent invention, used primarily to secure laptop computers. • Protein crystal structure determination would for them never be anything but a routine tool. • Molecular biology would never have been a discipline in its own right. Instead, it would always have been a set of techniques, introduced to students in better high schools. • They cannot imagine a world without kits to make experiments virtually automatic. • Since the first free-living organism had its genome sequenced when they were 7 years old, they have grown up in the age of genomics. They have had access to the complete sequence of the human genome since they were in middle school. • They have never attended a lecture given with slides from a carousel projector, and they may not have ever seen one given from overhead transparencies either. PowerPoint has been in use for virtually their entire lives. • In their lifetime, no one has ever pipetted anything by mouth. • DNA sequencing, peptide synthesis, chemical analysis, and gene synthesis have always been farmed out to specialty companies rather than done in one's own lab. • They have almost certainly never seen anyone blow glass. In fact, many of them may not know that test tubes were ever made of anything but plastic. • They have always had the option of going into the biotechnology industry. • The term 'enzyme' has always referred to both protein and RNA. • Evolution has always been under attack, and science and religion have largely been seen as incompatible. • There have always been 'big science' projects in biology. • Chemistry has always been a declining field in terms of student interest, and physics has always been the province of a small number of practitioners. • Believe it or not, they have never known a world without cDNA microarrays. • For them, 'Xerox' is a verb, Polaroid makes LCD TVs, and every piece of equipment is computer-controlled. • They have never requested a reprint. They probably don't know what one is. • They believe that no science was done before 2000. Any science not indexed on PubMed was not done either, even if it was done yesterday. • They cannot imagine that there once was only a single Cell journal, and just one Nature as well. I'm sure you could think of lots more. I know I could, but we had 10 feet of snow last night, and that 50-mile walk to school is going to take me a while.

766 citations

Journal Article
TL;DR: In this paper, a few and single-layered BN nanoribbons, mostly terminated with zigzag edges, can be produced under unwrapping multi-walled Bn nanotubes through plasma etching.
Abstract: Inspired by rich physics and functionalities of graphenes, scientists have taken an intensive interest in two-dimensional (2D) crystals of h-BN (analogue of graphite, so-called "white" graphite). Recent calculations have predicted the exciting potentials of BN nanoribbons in spintronics due to tunable magnetic and electrical properties; however no experimental evidence has been provided since fabrication of such ribbons remains a challenge. Here, we show that few- and single-layered BN nanoribbons, mostly terminated with zigzag edges, can be produced under unwrapping multiwalled BN nanotubes through plasma etching. The interesting stepwise unwrapping and intermediate states were observed and analyzed. Opposed to insulating primal tubes, the nanoribbons become semiconducting due to doping-like conducting edge states and vacancy defects, as revealed by structural analyses and ab initio simulations. This study paves the way for BN nanoribbon production and usage as functional semiconductors with a wide range of applications in optoelectronics and spintronics.

577 citations

01 Jan 2010
TL;DR: This journal special section will cover recent progress on parallel CAD research, including algorithm foundations, programming models, parallel architectural-specific optimization, and verification, as well as other topics relevant to the design of parallel CAD algorithms and software tools.
Abstract: High-performance parallel computer architecture and systems have been improved at a phenomenal rate. In the meantime, VLSI computer-aided design (CAD) software for multibillion-transistor IC design has become increasingly complex and requires prohibitively high computational resources. Recent studies have shown that, numerous CAD problems, with their high computational complexity, can greatly benefit from the fast-increasing parallel computation capabilities. However, parallel programming imposes big challenges for CAD applications. Fully exploiting the computational power of emerging general-purpose and domain-specific multicore/many-core processor systems, calls for fundamental research and engineering practice across every stage of parallel CAD design, from algorithm exploration, programming models, design-time and run-time environment, to CAD applications, such as verification, optimization, and simulation. This journal special section will cover recent progress on parallel CAD research, including algorithm foundations, programming models, parallel architectural-specific optimization, and verification. More specifically, papers with in-depth and extensive coverage of the following topics will be considered, as well as other topics relevant to the design of parallel CAD algorithms and software tools. 1. Parallel algorithm design and specification for CAD applications 2. Parallel programming models and languages of particular use in CAD 3. Runtime support and performance optimization for CAD applications 4. Parallel architecture-specific design and optimization for CAD applications 5. Parallel program debugging and verification techniques particularly relevant for CAD The papers should be submitted via the Manuscript Central website and should adhere to standard ACM TODAES formatting requirements (http://todaes.acm.org/). The page count limit is 25.

459 citations