Top PDF Semiconductor Devices: Theory and Application

Semiconductor Devices: Theory and Application

Semiconductor Devices: Theory and Application

The LED has displaced traditional incandescent (filament-based) light sources in many applications due to its high efficiency in turning an electrical energy input into a light output. They are small, physically robust, operate relatively cool and are available in a number of different colors. The schematic symbol is shown in Figure 2.25. The basic idea behind its operation is fairly simple. In a forward-biased PN junction, when free electrons recombine and “fall” into lower energy valence holes they must give up this energy differential in some manner. In most diodes, this energy is emitted as heat. In LED s, the energy transition is designed such that it is radiated at shorter wavelengths (i.e., visible light). In order to achieve this, LED s are not formed just using silicon as in a typical switching diode. Instead, somewhat more exotic materials are used. From an analysis or design standpoint, the important thing to remember is that the forward voltage tends to be noticeably higher than silicon's 0.7 volt drop. The precise value will depend on the material, which in turn effects the color. A generic red LED will likely exhibit a forward drop of around 1.8 volts or so. Other colors tend to be somewhat higher as we move through the 8 There are advantages to using the infrared over the visible spectrum for this application.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Clawson and Reese-Weber’s study (2003) examined the relationship between sexual risk-taking behaviors and the timing of parent-adolescent sexual communication. The study, based on Socialization Theory (Philliber, 1980), documented that timing is an important factor in predicting sexual risk-taking behavior. Two hundred and fourteen participants (101 males and 113 females) between the ages of 18 and 21 years of age completed the study questionnaire for extra course credit; the sample was 82% White and 9% African American. Clawson and Reese-Weber (2003) concluded that emphasis should be placed on encouraging parents to discuss sexuality early in their adolescents’ development, preferably prior to initiation of sexual activity. The study also suggested several areas for additional research including having a sample with more diversity, especially looking at African American adolescents, who are more likely to be sexually active then Whites (CDC, 2010). Future research should also focus on identifying if discussion of certain topics (e.g., pregnancy, sexually transmitted infections) are more strongly correlated with sexual risk-taking behavior than others (e.g., prostitution), and investigating the specific content of parent-child sexual risk communication and perceived parental attitudes related to discussions (Clawson & Reese-Weber, 2003).
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Effects of ionizing radiation on nanomaterials and III-V semiconductor devices.

Effects of ionizing radiation on nanomaterials and III-V semiconductor devices.

Devices based on III-V semiconductors and nanomaterials are expected to be critical components of future microsystems as the demand for greater functionality, range of application, and robustness continue to increase. There currently is a need for small-scale power supplies which can be used to power microsystems thereby enabling autonomous functionalities. The use of III-V semiconductor-based solid state devices and nanomaterials to convert the radiant energy of a radioisotope source into electricity has been investigated as a viable option to fulfill this demand. The energy imparted to a material by incident alpha-particles, resulting in electron-hole pair formation and ionization, may be converted into usable electrical power by a radioisotope microbattery (RIMB). A model describing the spatially varying rate of ionizing energy deposited in an absorber material held in close proximity to an isotropic alpha-emitting radioisotope source has been developed. The alpha-particle energy deposition model (ADEP) allows the total energy exciting the RIMB devices to be calculated and thereby provides a means to determine the efficiency of the experimentally measured devices. Two RIMB designs are investigated including a direct conversion microbattery based on a nipi-diode structure and an indirect conversion microbattery employing radioluminescent nanophosphors.
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Future Semiconductor Devices for Multi Valued Logic Circuit Design

Future Semiconductor Devices for Multi Valued Logic Circuit Design

This paper introduces future devices for multi-valued logic implementation. Quantum dot gate field effect transistor (QDGFET) works based on the change in threshold voltage due to stored charge in the quantum dots in the gate region. Quantum dot channel field effect transistor (QDCFET) produces more number of states in their transfer characteristics because of charge flow through the mini-band structure formed by the overlapping energy bands of the neighboring quantum dots in the channel region of the FET. On the other hand spatial wave-function switched field effect transistor (SWSFET) produces more number of states in its transfer characteristic based on the switching of charge carriers from one channel to other channel of the device. In this paper we discuss QDGFET, QDCFET and SWSFET in detail to ex- plore their application in future multi-valued logic circuits.
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Two contact semiconductor devices for ultra fast switching and synchronisation

Two contact semiconductor devices for ultra fast switching and synchronisation

For small negative detunings the NLOA exhibits unstable behaviour, see Figure 3.17 showing the output on a real-time scope, which is thought to be due to the gain dispersion effects similar to those found in single section SOA's [3.23, 3.24, 3.25]. The output has two stable states but does not exist in either continuously and swaps between them in a random manner; this region of operation is not suitable for telecommunication systems application. This behaviour will be referred to as 'dispersive switching' after the initial SOA results although it must be recognised that the dynamics and causes are much more complicated than this simple definition would indicate; see Chapter 2. These dispersive effects aie particularily evident at 1.57 pm where this behaviour was observed over a range of -1.5 GHz. As the wavelength was tuned to shorter wavelengths this range reduces until at 1.585 pm this behaviour was not observed at this power. It is thought that at this wavelength the material gain is too low for this input power to induce sufficient gain saturation. It is shown later. Figure 3.20, that increasing the input power may well result in increased dispersive behaviour. For further negative detunings only linear amplification is seen and the gain decreases rapidly with detuning. Comparing this experimental variation of device gain with detuning against a theoretical plot shown in Figure 2.28 it is clear that there is good agreement, even on the order of magnitude.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

In the 1950’s, social scientists saw a need to quantify the methods of their sciences, such as sociology and anthropology. Thus many adopted terms and concepts from graph theory to help describe problems they faced. They used these ideas to help cre- ate models as well as analyze collected empirical data, linking graph theoretical ideas with social ideas such as “status, influence, cohesiveness, social roles, and identities in social networks,” [5] page 3. Around the same time, graphs became an accepted model for means of disease and information transmission. Furthermore, it was around this time that the notion of random graphs saw its early developments. This new approach saw graphs as stochastic, or probabilistic, objects rather than deterministic. All these events thus produced a surge of interest in the new field of network science. [5] chapter 1. Before any further discussion of the historical development of network science, it is important to introduce several basic concepts from graph theory. For a complete introduction to graph theory, see e.g. Diestel’s book Graph Theory [9].
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Over the past 15 years, health aid has changed significantly. These changes include a shift of paradigm from international to global health. International health encompasses the application of the principles of public health to problems and challenges that affect low- and middle-income countries. It often focuses on addressing infectious and tropical diseases, water and sanitation, malnutrition, and maternal and child health (Ooms et al., 2011). Global health places a priority on improving health and achieving equity in health for all people worldwide. It is based on the assumption that countries can no longer “see health as a concern limited by national borders, as they often did in the past.” (Elmendorf, 2010). The "global" in global health refers to the scope of the health problems regardless of where they occur (Koplan et al., 2009).
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Terahertz Generation in Submicron Nitride-based Semiconductor Devices

Terahertz Generation in Submicron Nitride-based Semiconductor Devices

The development of technology based on GMR, a phenomenon first reported in 1988 [60], has been the most commercially viable application to date. GMR occurs in a multi-layered structures composed of a non-ferromagnetic layer sandwiched between two ferromagnetic layers. The ferromagnetic layers naturally align themselves in an anti-parallel state. As electrons with mixed spin states pass through the structure they experience a large amount of scattering. In the presence of a magnetic field, the ferromagnetic layers are aligned in a parallel state and the population of electrons with parallel spins pass through with less scattering, leading to a decrease in the electrical resistance of the structure. The near ubiquitous application of GMR to hard drive sensing technology led to a dramatic increase of drive storage size and had an undeniable effect on the current state of computing [55].
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Ecosystem structure and function are the product of biological and ecological elements and their connections and interactions. Understanding structure and process in ecosystems is critical to ecological studies. Ecological networks, based on simple concepts in which biological and ecological elements are depicted as nodes with relationships between them described as links, have been recognized as a valuable means of clarifying the relationship between structures and process in ecosystems. Ecological network analysis has benefited from the advancement of techniques in social science, computer science, and mathematics, but attention must be paid to whether the designs of these techniques follow ecological principles and produce results that are ecologically meaningful and interpretable. The objective of this dissertation is to examine the suitability of these methods for various applications addressing different ecological concerns. Specifically, the studies that comprise this dissertation test methods that reveal the structure of various ecological networks by decomposing networks of interest into groups of nodes or aggregating nodes into groups. The key findings in each specific application are summarized below.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

This thesis presents an alternative to traditionally-used coprocessors to examine how well a data intensive application of short read mapping maps to a DSP coprocessor technology. The basis for short read mapping is built upon the Burrows-Wheeler Transform (BWT) [2]. Originally designed for data compression, the BWT reorganizes a block of text placing similar characters together. While optimized for data compression, it was additionally determined to be an effective solution for searching strings as well. The Bowtie project [3] developed a short read mapping algorithm based upon the BWT to increase performance in searching for short reads in a large reference genome. Analyzing the repetitive computations performed in Bowtie, an algorithm was developed for a GPU implementation improving the exact match short read mapping by the use of table based searches [4].
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

However, ferritic alloys have also been observed to have a somewhat non-uniform nanoparticle dispersion, be difficult to manufacture, and susceptible to embrittlement at high temperatures due to an undesirable phase transformation between 400°C and 550°C [12], [10]. 9Cr ODS is unique in that there is the observed formation of a non- equilibrium phase, designated as the residual ferrite, which serves to greatly enhance several vital mechanical properties in comparison to both standard RAFM alloys and the fully ferritic 18Cr ODS. This is theorized to be further enhanced by sliding at weaker regions such as at the grain boundaries and packet boundaries; behaving as a fiber composite material comprising the harder residual ferrite and the softer tempered martensite. [15] A martensitic alloy, such as 9Cr ODS, would be best utilized in areas exposed to high temperatures, neutron doses, and mechanical strain, such as fuel cladding within the reactor pressure vessel. 18Cr ODS would be more valuable for application as structural components that are in contact with coolant, as the high chromium content lends to good resistance to corrosion.
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

opposed to Removal simply reinforced the rhetoric of an out of touch intelligentsia, awash in abstraction and theory, devoid of the practically acquired knowledge that was the true national virtue—the virtue of Jackson. This identity claimed by the Democrats emerges throughout Jacksonian politics, whether it was the presidents’ struggles against the machinations of Supreme Court legal theorizing or his efforts against that ultimate sandcastle, the National Bank. The Indian Removal debate occurs at the incipient stages of partisan identity formation and was, as Rolater demonstrated, an issue of constant party conflict throughout the 1830s. The discourse of Indian Removal did not take on this pattern because it was already present. The dynamic grew within the arguments themselves, a natural outgrowth of regional animosity/identity and of the claims to a new authority made by “experts.” The process of pro-Removal argumentation was appealing because it established a sense of oneself as being on the side of the inherited practical, national, knowledge. The caricature of the opposition, emphasized through rhetoric that was often both sarcastic and/or humorous, further reinforced this identity which was embedded in a certain version of the American story. The “science” of the vanishing Indian corresponded to the myth of the frontier.
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Semiconductor Devices and Electronic World

Semiconductor Devices and Electronic World

One of the noteworthy things about this field, as in many other areas of technology, is how little the fundamental principles changes over time. Systems are incredibly smaller, current speeds of operation are truly remarkable, and new gadgets surface every day, leaving us to wonder where technology is taking us. However, if we take a moment to consider that the majority of all the devices in use were invented decades ago and that design techniques appearing in texts as far back as the 1930s are still in use, we realize that most of what we see is primarily a steady improvement in constructions techniques, general characteristics, and application techniques rather than the development of new elements and fundamentally new designs. The result is that most of the devices discussed in this text have been around for some time, and that tests on the subject written a decade ago are still good references with content that has not changed very much. The major changes have been in the understanding of how these devices work and their full range of capabilities, and in improved methods of teaching the fundamentals associated with them. The benefit of all this to the new student of the subject is that the material in this text will, we hope, have reached a level where it is relatively easy to grasp and the information will have application for years to come.
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Simulating nanoscale semiconductor devices

Simulating nanoscale semiconductor devices

methods trace out the solution curve z(a), parameterized by a, so that G (z(a), a) = 0. For our particular application, we are solving W (f, V) = 0, where f is the steady-state electron distribution, and the voltage drop V is the parameter. Numerically, continuation methods generate two sequences: a sequence of parameters {V i } (in our case, voltage drops) with

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The Application Of Nanotechnology In The Semiconductor Industry : The Case Of Advanced Micro Devices (AMD) Global Services Sdn. Bhd.

The Application Of Nanotechnology In The Semiconductor Industry : The Case Of Advanced Micro Devices (AMD) Global Services Sdn. Bhd.

All praise are due to Allah S.W.T who had given blessing, strength, and knowledge in finishing this research entitled „the application of nanotechnology in the semiconductor industry: the case of Advanced Micro Devices (AMD) Global Services Sdn. Bhd.‟ Slawat and salam also propose to the Prophet Muhamad SAW, the Uswatun Hasanah for all Moslems.

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Novel optoelectronic devices based on single semiconductor nanowires (nanobelts)

Novel optoelectronic devices based on single semiconductor nanowires (nanobelts)

Semiconductor nanowires (NWs) or nanobelts (NBs) have attracted more and more attention due to their potential application in novel optoelectronic devices. In this review, we present our recent work on novel NB photodetectors, where a three-terminal metal – semiconductor field-effect transistor (MESFET) device structure was exploited. In contrast to the common two-terminal NB (NW) photodetectors, the MESFET-based photodetector can make a balance among overall performance parameters, which is desired for practical device applications. We also present our recent work on graphene nanoribbon/semiconductor NW (SNW) heterojunction light-emitting diodes (LEDs). Herein, by taking advantage of both graphene and SNWs, we have fabricated, for the first time, the graphene-based nano-LEDs. This achievement opens a new avenue for developing graphene-based nano-electroluminescence devices. Moreover, the novel graphene/SNW hybrid devices can also find use in other applications, such as high-sensitivity sensor and transparent flexible devices in the future.
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Transient electrothermal simulation of power semiconductor devices

Transient electrothermal simulation of power semiconductor devices

T HE ELECTRICAL behavior of power semiconductor de- vices is greatly dependent on package design. A good package of switching power devices should provide not only solid electrical isolation from semiconductor chip to supporting baseplate but also good thermal performance to limit the junc- tion temperature rise. The solid electrical isolation is achieved by having the isolator integrated into the package. Thermal per- formance is related with specific structure and the material used in the package design. Thermal performance is one of the most crucial issues of package technology for power semiconductor devices. According to some research [1], nearly 60% of failures are temperature-induced, and for every 10 ◦ C temperature rise in the operating environment, the failure rate nearly doubles. The thermal performance of packaging technology is simply eval- uated by the maximum temperature rise in the semiconductor
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Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

Modeling of Sic Power Semiconductor Devices For Switching Converter Applications

The power Schottky diode model is a simple physics-based model comprised of a voltage controlled current source, a temperature dependent drift region resistance and a nonlinear capacitance. A detailed parameter extraction procedure for a simple physics- based power SiC Schottky diode model is presented. The proposed parameter extraction procedure includes the extraction of doping concentration, active area and thickness of drift region, which are needed for the proposed physics-based power Schottky diode model. The main advantage is that this procedure does not require any knowledge of device fabrication. The only measurements required for the parameter extraction are a simple static I-V characterization and C-V measurements. Validity of the approach is verified by comparison of simulated and experimental results at temperatures from 25º C to 175º C for four different devices from two different manufacturers which are shown in the first paragraph. Inductive switching validation also shows that the model has a fairly good match with experiments. This means that the model presented in this dissertation is general and can be used for devices with widely different voltage and current ratings.
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Conductance enhancement in quantum point contact semiconductor superconductor devices

Conductance enhancement in quantum point contact semiconductor superconductor devices

tween the Andreev reflection and the mesoscopic effects seen in mesoscopic semiconductor structures. 3,4 In recent years the technological efforts have revealed a variety of new me- soscopic phenomena, see Refs. 4–7, and references therein. One class of the studied devices are the quantum point con- tact 共 QPC 兲 2DEG-S and S-2DEG-S devices with the QPC in the normal region. The dc Josephson effect and the quanti- zation of the critical current in QPC S-2DEG-S junctions have been studied extensively both experimentally by, e.g., Takayanagi and co-workers 8 and theoretically by, e.g., Beenakker and van Houten, 9,10 Beenakker, 11 and Furusaki, Takayanagi, and Tsukada. 12
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Ferroelectric HfO2 for Emerging Ferroelectric Semiconductor Devices

Ferroelectric HfO2 for Emerging Ferroelectric Semiconductor Devices

deposited. 5 nm of aluminum was finally evaporated. An attempt was also made using the sputter system without breaking the vacuum. However, during the development of the exposed resist, the Al layer was developed away, which could indicate a porous film. This may be because of the low power used to sputter Al. Without sufficient energy to coalesce, the atoms might just have simply hit the wafer and adsorbed, leading to a low quality film. Evaporated Al, on the other hand, has more thermal energy and the atoms can form a dense film. After the first lithography, 15 nm of TiN was sputtered on samples G and H and then lifted-off. Different methods and temperatures of annealing were tried on each sample: 1 h at 600 ◦ C in a nitrogen furnace, 20 sec at 850 ◦ C in RTA and 1 sec at 1000 ◦ C in RTA. The rest of the process is similar to sample D and the final devices schematic can be seen in Figure 6.6 .
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