Showing papers by "Muhammad Mustafa Hussain published in 2011"
TL;DR: The proposed silicon nanotube field effect transistor offers the true potential to be an ideal blend for quantum ballistic transport study of device property control by bottom-up approach and high-density integration compatibility using top-down state-of-the-art complementary metal oxide semiconductor flow.
Abstract: We introduce the concept of a silicon nanotube field effect transistor whose unique core–shell gate stacks help achieve full volume inversion by giving a surge in minority carrier concentration in the near vicinity of the ultrathin channel and at the same time rapid roll-off at the source and drain junctions constituting velocity saturation-induced higher drive current-enhanced high performance per device with efficient real estate consumption. The core–shell gate stacks also provide superior short channel effects control than classical planar metal oxide semiconductor field effect transistor (MOSFET) and gate-all-around nanowire FET. The proposed device offers the true potential to be an ideal blend for quantum ballistic transport study of device property control by bottom-up approach and high-density integration compatibility using top-down state-of-the-art complementary metal oxide semiconductor flow.
140 citations
10 Apr 2011
TL;DR: In this paper, the impact of device scaling on the electrical and mechanical properties of metal contacts in NEMS devices has been thoroughly investigated in the literature, and the authors highlight the performance and reliability degradations of such metal contacts caused by scaling.
Abstract: Nano-electro-mechanical switches (NEMS) offer new possibilities for the design of ultra energy-efficient systems; however, thus far, all the fabricated NEMS devices require high supply voltages that limit their applicability for logic designs. Therefore, research is being conducted to lower the operating voltages by scaling down the physical dimensions of these devices. However, the impact of device scaling on the electrical and mechanical properties of metal contacts in NEMS devices has not been thoroughly investigated in the literature. Such a study is essential because metal contacts play a critical role in determining the overall performance and reliability of NEMS. Therefore, the comprehensive analytical study presented in this paper highlights the performance and reliability degradations of such metal contacts caused by scaling. The proposed modeling environment accurately takes into account the impact of roughness of contact surfaces, elastic/plastic deformation of contacting asperities, and various inter-molecular forces between mating surfaces (such as Van der Waals and capillary forces). The modeling results are validated and calibrated using available measurement data. This scaling analysis indicates that the key contact properties of gold contacts (resistance, stiction and wear-out) deteriorate “exponentially” with scaling. Simulation results demonstrate that reliable (stiction-free) operation of very small contact areas (≈ 6nm × 6nm) will be a daunting task due to the existence of strong surface forces. Hence, contact degradation is identified as a major problem to the scaling of NEMS transistors.
22 citations
Proceedings Article•
14 Jun 2011TL;DR: In this article, electron mobility on (100 and (110) planar FETs and SOI FinFETs was evaluated and it was experimentally demonstrated that the finetuning process does not present a drawback in terms of electron mobility.
Abstract: Electron mobility on (100) and (110) planar FETs and SOI FinFETs was evaluated. It is experimentally demonstrated that the (110) sidewall of FinFETs does not present a drawback in terms of electron mobility - contrary to results obtained on (110) planar MOSFETs. This is comprehensively explained by a combination of first principles and empirical approach closely matching the experimental data.
17 citations
TL;DR: High-selectivity, uniform three-dimensional (3D) flower-like bismuth telluride (Bi(2)Te(3)) nanocrystals consisting of few-quintuple-layer nanoplatelets with a thickness down to 4.5 nm were synthesized for the first time by a facile, one-pot polyol method with acetic acid as the structure-director.
10 citations
TL;DR: The impact of contact materials on the performance of nanostructured devices is expected to be significant as discussed by the authors, especially since size scaling can increase the contact resistance and induce many unseen phenomenon and reactions that greatly impact device performance.
Abstract: The impact of contact materials on the performance of nanostructured devices is expected to be significant. This is especially true since size scaling can increase the contact resistance and induce many unseen phenomenon and reactions that greatly impact device performance. Nanowire and nanoelectromechanical switches are two emerging nanoelectronic devices. Nanowires provide a unique opportunity to control the property of a material at an ultra-scaled dimension, whereas a nanoelectromechanical switch presents zero power consumption in its off state, as it is physically detached from the sensor anode. In this article, we specifically discuss contact material issues related to nanowire devices and nanoelectromechanical switches.
7 citations
Patent•
21 Jul 2011
TL;DR: In this paper, a self-powered device (100) using on-chip power generation is described, which includes a substrate (118), a power generation module (114, 106, 110, 112), and a power storage module (108) on the substrate.
Abstract: An apparatus, system, and method for a self-powered device (100) using on-chip power generation. In some embodiments, the apparatus includes a substrate (118), a power generation module (114, 106, 110, 112) on the substrate, and a power storage module (108) on the substrate. The power generation module may include a thermoelectric generator (106) made of bismuth telluride.
7 citations
Patent•
19 Jul 2011TL;DR: In this article, an apparatus, system, and method for a thermoelectric generator is described, where the generator is coupled to a first and a second conductor, and a third conductor may be coupled to the second conductor.
Abstract: An apparatus, system, and method for a thermoelectric generator. In some embodiments, the thermoelectric generator comprises a first thermoelectric region and a second thermoelectric region, where the second thermoelectric region may be coupled to the first thermoelectric region by a first conductor. In some embodiments, a second conductor may be coupled to the first thermoelectric region and a third conductor may be coupled to the second thermoelectric region. In some embodiments, the first conductor may be in a first plane, the first thermoelectric region and the second thermoelectric region may be in a second plane, and the second conductor and the third conductor may be in a third plane.
6 citations
22 Feb 2011
5 citations
24 Apr 2011
TL;DR: In this paper, the authors present a design, simulation results and fabrication of electromechanical switches enabling parallel data processing and multi functionality, applied in logic gates AND, NOR, XNOR, and Flip-Flops.
Abstract: We present a design, simulation results and fabrication of electromechanical switches enabling parallel data processing and multi functionality. The device is applied in logic gates AND, NOR, XNOR, and Flip-Flops. The device footprint size is 2μm by 0.5μm, and has a pull-in voltage of 5.15V which is verified by FEM simulation.
3 citations
TL;DR: The structural architecture of the newly designed switch consists of a pinned flexural beam structure which allows low strain lateral actuation for enhanced mechanical integrity and true parallel beam deflection, and lithographically defined contact area to prevent possible device welding.
Abstract: We report on the design and modeling of novel nano electromechanical switches suitable for implementing reset/set flip-flops, AND, NOR, and XNOR Boolean functions. Multiple logic operations can be implemented using only one switching action enabling parallel data processing; a feature that renders this design competitive with complementary metal oxide semiconductor and superior to conventional nano-electromechanical switches in terms of functionality per device footprint. The structural architecture of the newly designed switch consists of a pinned flexural beam structure which allows low strain lateral actuation for enhanced mechanical integrity. Reliable control of on-state electrical current density is achieved through the use of metal-metal contacts, true parallel beam deflection, and lithographically defined contact area to prevent possible device welding. Dynamic response as a function of device dimensions numerically investigated using ANSYS and MatLab Simulink.
3 citations
TL;DR: For the first time in this work, the signal analysis in frequency domain is applied to create the Fourier frequency spectra which was used to detect the sample properties and their recognition.
01 Jan 2011
TL;DR: In this article, Hasan et al. showed a comprehensive physical investigation using transmission electron microcopy/electron energy loss spectroscopy (TEM/EELS), x-ray diffraction (XRD), xray photoelectron spectrogram (XPS) and secondary ion mass spectroscopic (SIMS) to show replacement of oxygen by nitrogen in the metal/dielectric interface, formation of TiONx, reduction of Ti/N concentration and grain size increment happen with TiN thickness increment and thus may increase the work function.
Abstract: Work Function Tuning in Sub-20nm TiN Metal GateMechanism and Engineering Md. Mehedi Hasan Scaling of transistors (the building blocks of modern information age) provides faster computation at the expense of excessive power dissipation. Thus to address these challenges, high-k/metal gate stack has been introduced in commercially available microprocessors from 2007. Since then titanium nitride (TiN) metal gate’s work function (Wf) tunability with its thickness (thickness increases, work function increases) is a well known phenomenon. Many hypotheses have been made over the years which include but not limited to: trap charge and metal gate nucleation, nitrogen concentration, microstructure agglomeration and global stress, metal oxide formation, and interfacial oxide thickness. However, clear contradictions exist in these assumptions. Also, nearly all these reports skipped a comprehensive approach to explain this complex paradigm. Therefore, in this work we first show a comprehensive physical investigation using transmission electron microcopy/electron energy loss spectroscopy (TEM/EELS), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) to show replacement of oxygen by nitrogen in the metal/dielectric interface, formation of TiONx, reduction of Ti/N concentration and grain size increment happen with TiN thickness increment and thus may increase the work function. Then, using these finding, we experimentally show 100meV of work function modulation in