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The economic health of the semiconductor industry requires substantial scaling of chip power, performance, and area with every new technology node that is ramped into manufacturing in two year intervals. With no direct physical link to any particular design dimensions, industry wide the technology node names are chosen to reflect the roughly 70% scaling of linear dimensions necessary to enable the doubling of transistor density predicted by Moore's law and typically progress as 22nm, 14nm, 10nm, 7nm, 5nm, 3nm etc. At the time of this writing, the most advanced technology node in volume manufacturing is the 14nm node with the 7nm node in advanced development and 5nm in early exploration. The technology challenges to reach thus far have not been trivial. This review addresses the past innovation in response to the device challenges and discusses in-depth the integration challenges associated with the sub-22nm non-planar finFET technologies that are either in advanced technology development or in manufacturing. It discusses the integration challenges in patterning for both the front-end-of-line and back-end-of-line elements in the CMOS transistor. In addition, this article also gives a brief review of integrating an alternate channel material into the finFET technology, as well as next generation device architectures such as nanowire and vertical FETs. Lastly, it also discusses challenges dictated by the need to interconnect the ever-increasing density of transistors. [ABSTRACT FROM AUTHOR]

This paper reports on correlation of growth-related defects and electrical properties in GaSb films grown on different Si substrates using metamorphic buffers. Large lattice mismatch between GaSb and Si (∼11%) results in the formation of threading dislocations (TDs) and microtwins (MTs) along with antiphase domains due to the lack of inversion symmetry in III-V's. The defect density profiles were analyzed using transmission electron microscopy and atomic force microscopy. The TD density of just below 108 cm-2 and MT density below 104 cm-1 were found in 2.1 μm thick structures, and were found to be four times higher than in similar GaSb structures on GaAs substrates. Hole density and mobility profiles were obtained using differential Hall method and show that dislocations (TDs or MT partials) generate about 25 acceptors/nm. Minimum midgap interface trap density values are similar in the metal-oxide-semiconductor structures prepared on GaAs and Si, ∼2 x 1012 cm2 eV-1. [ABSTRACT FROM AUTHOR]

A study of heteroepitaxial molecular beam epitaxy growth of strained p-channel InGaSb quantum well (QW) on lattice mismatched Si (100) using Al(Ga)Sb metamorphic buffers is presented in this paper. The migration enhanced epitaxy (MEE) technique was employed for AlSb nucleation layer (NL) on Si and analyzed using atomic force microscopy and in-situ Auger electron spectroscopy techniques to optimize growth conditions for continuous 2D buffer layers and improve surface quality of subsequent layers. Growth-related defects (threading dislocations, microtwins, and antiphase boundaries) and their effect on surface morphology and electrical properties of the QWs are analyzed with scanning electron microscope and transmission electron microscopy and correlated to the NL properties. The baseline data for defect density in the layers and resultant surface morphology are presented. Room temperature p-channel Hall mobility of 660cm²/V s at 3×1011 cm-2 sheet hole concentration is achieved in InGaSb QWs using an optimized 15 monolayer AlSb MEE NL at 300°C growth temperature. [ABSTRACT FROM AUTHOR]

Abstract: The nanostructures and magnetic properties of Ge1−x Mn x thin films grown on Si substrates by molecular beam epitaxy, with different nominal Mn concentrations (1−4%) and different growth temperatures, have been systematically investigated by transmission electron microscopy and superconducting quantum interference device. It was discovered that when Ge1−x Mn x thin films were grown at 70°C, with increase in Mn concentration, Mn-rich tadpole shaped clusters started to nucleate at 1% Mn and become dominate in the entire film at 4% Mn. While for the thin films grown at 150°C, tadpoles was firstly seen in the film with 1% Mn and subsequently Mn-rich secondary precipitates became dominant. The magnetic properties show specific features, which are mainly related to the nature and amount of Mn-rich clusters/precipitates within these thin films. [ABSTRACT FROM AUTHOR]