Role In Semiconductor Devices Research Articles

The Role of Semiconductor Devices in the Development of High-Performance Computing Systems: Challenges in Scaling and Heat Dissipation

The Role of Semiconductor Devices in the Development of High-Performance Computing Systems: Challenges in Scaling and Heat Dissipation

Resolving trapping effects by scanning microwave microscopy

Trapping effects are playing an essential role in semiconductor devices. The localization of trapping effects with a high spatial resolution can provide valuable information on the interface and oxide quality in state of the art semiconductor devices. On the example of a Si diode with suspected oxide traps, a method based on Scanning Microwave Microscopy (SMM) is shown to resolve charge carriers, which accumulate within the silicon due to trapping effects at the Si/SiO2 interface.

The effect of illumination and electrode adjustment on the carrier behavior in special multilayer devices

Intermediate connectors play an important role in semiconductor devices, especially in tandem devices. In this paper, four types of different intermediate connectors (e.g. Mg:Alq3/MoO3, MoO3, Mg:Alq3, and none) and two kinds of modified electrode materials (LiF and MoO3) integrated into the special multilayer devices are proposed, with the aim of studying the impact of light illumination and electrode adjustment on the carrier behavior of intermediate connectors through the current density–voltage characteristics, interfacial electronic structures, and capacitance–voltage characteristics. The results show that the illumination enhances the charge generation and separation in intermediate connectors, and further electrode interface modifications enhance the functionality of intermediate connectors. In addition, the device with an efficient intermediate connector structure shows a photoelectric effect, which paves the way for organic photovoltaic devices to realize optical-electrical integration transformation.

Visualizing excitations at buried heterojunctions in organic semiconductor blends

Interfaces play a crucial role in semiconductor devices, but in many device architectures they are nanostructured, disordered and buried away from the surface of the sample. Conventional optical, X-ray and photoelectron probes often fail to provide interface-specific information in such systems. Here we develop an all-optical time-resolved method to probe the local energetic landscape and electronic dynamics at such interfaces, based on the Stark effect caused by electron-hole pairs photo-generated across the interface. Using this method, we found that the electronically active sites at the polymer/fullerene interfaces in model bulk-heterojunction blends fall within the low-energy tail of the absorption spectrum. This suggests that these sites are highly ordered compared with the bulk of the polymer film, leading to large wavefunction delocalization and low site energies. We also detected a 100 fs migration of holes from higher- to lower-energy sites, consistent with these charges moving ballistically into more ordered polymer regions. This ultrafast charge motion may be key to separating electron-hole pairs into free charges against the Coulomb interaction.

Studies on Dielectric Properties of Annealed RF-Sputtered ZrO2 Thin Films

Dielectrics play an important role in semiconductor devices when it is used as gate insulator MOS transistors or in memory applications [1]. SiO2 has been one of the most typically used dielectrics due to its good properties like electrical and thermodynamic stability. It provides a great Si-SiO2 interface used in MOS transistors, and has high quality isolation electrical characteristic. Despite its benefits, there comes a point where continuous device scaling sets a limit to what materials can be used. Therefore, other high-k gate dielectric materials have to be found in order to go below 1.5nm thickness when SiO2 is used for the 45nm node technology. ZrO2 is one of the high-k materials that can be used as a possible solution [2]. ZrO2 possesses some interesting characteristics like relatively high-k and wide bandgap. In addition, its crystal structure changes at different temperatures, going from monoclinic to tetragonal and then to cubic as the temperature raises. Even though the monoclinic structure is stable and occurs at room temperature, the other two are not. This presents some problems, which create phase instability leading to stresses and cracking of the material. However, by introducing certain rare earth oxide based dopants as for example Yttria (Y2O3), stable phases for the tetragonal and cubic structures can be achieved, as well as increasing the permittivity constant of the dielectric [3,4]. In this work, ZrO2 thin films are deposited on glass substrates to find various properties. The films are prepared in an RF magnetron sputtering system using a 99.5% pure yttria-stabilized zirconium oxide target. ZrO2 based metal/insulator/metal (MIM) structures are fabricated using Aluminum as the top and bottom electrodes. Various electrical properties are investigated for the ZrO2 films prepared under different deposition and annealing conditions. REFERENCES [1] G. D. Wilk, R. M. Wallace, J. M. Anthony, “High-κ gate dielectrics: Current status and materials properties considerations” Journal of Applied Physics, Vol 89, 2001 [2] M. K. Bera, C. K. Maiti, "Reliability of Ultra-thin Zirconium Dioxide (ZrO2) Films on Strained-Si" Physical and Failure Analysis of Integrated Circuits, 2006. [3] S. M. Hwang, S. M. Lee, K. Park, M. S. Lee, J. Joo, J. H. Lim, H. Kim, J. J. Yoon, Y. D. Kim “Effect of annealing temperature on microstructural evolution and electrical properties of sol-gel processed ZrO2 /Si films” Applied Physics Letters 98, 2011 [4] H. García, H. Castán, S. Dueñas, E. Pérez, L. Bailón, “Electrical characterization of MIS capacitors based on DY203-doped Zr02 dielectrics”, Electron Devices (CDE), 2015

Silicides and Their Role in Semiconductor Devices

Silicides and Their Role in Semiconductor Devices

The impact of semiconductor devices on electrical power engineering

The differences in approach between power engineering and electronic engineering are briefly outlined and the role of semiconductor devices in place of those based on the mercury-arc is discussed. Applications of the diode and thyristor to d.c. and a.c. machines are described together with the use of thyristors in high voltage d.c. power transmission. The importance of careful integration of semiconductor devices with the associated machines in any proposed scheme is emphasised.

The expanding role of semiconductor devices in telecommunications

The junction transistor made its first impact on telecommunications in transmission systems, then entirely analogue, effectively by replacing thermionic valves. later developments of that transistor have made possible systems enabling over 10 000 telephone channels to be carried on one 9.5 mm diameter coaxial tube. submarine cable systems have also benefited from the development of highly reliable wideband transistors, with a 1800-circuit single-cable system now in production for intercontinental working. recently, telecommunications satellites, owing their success electronically to several different classes of semiconductor device, have challenged repeatered cables, offering even higher capacities.Exploitation of the transistor as a logic or switching device followed the early analogue applications, with 24-channel digital transmission systems using pulse code modulation. the control of switching systems was soon demonstrated, with intensive follow-up, even though metallic contacts through which the audio signals are routed in public telephone exchanges have not yet been supplanted.Some systems under development demand special devices, e.g. solid-state sources for frequencies up to 100ghz for both guided and new free-space microwave systems. guided optical communications make desirable a long life, room-temperature-operated, high duty ratio gallium arsenide laser. integrated circuits will find a very wide range of use throughout.