Simulation of Ionization/Displacement Synergistic Effect on Bipolar Transistors under Different Processes conditions

There is extensive interest in SiGe for use in heterojunction bipolar transistors. SiGe/Si superlattices are also of interest because of their potential for use in infrared detectors and field-effect transistors. The processing required for these materials is quite compatible with existing silicon technology. However, before SiGe can be used extensively for devices, there is a need to understand and then control the origin and behavior of defects in the materials. The present study was aimed at investigating the structural quality of, and the behavior of defects in, graded SiGe layers grown by chemical vapor deposition (CVD).The structures investigated in this study consisted of Si1-xGex[x=0.16]/Si1-xGex[x= 0.14, 0.13, 0.12, 0.10, 0.09, 0.07, 0.05, 0.04, 0.005, 0]/epi-Si/substrate heterolayers grown by CVD. The Si1-xGex layers were isochronally grown [t = 0.4 minutes per layer], with gas-flow rates being adjusted to control composition. Cross-section TEM specimens were prepared in the 110 geometry. These were then analyzed using two-beam bright-field, dark-field and weak-beam images. A JEOL JEM 200CX transmission electron microscope was used, operating at 200 kV.

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TEM study of phosphorus-implanted pseudomorphic Si0.88Ge0.12 on Si(100)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138713 ◽

1995 ◽

Vol 53 ◽

pp. 468-469

Author(s):

N. David Theodore ◽

Donald Y.C Lie ◽

J. H. Song ◽

Peter Crozier

Keyword(s):

Integrated Circuits ◽

Heterojunction Bipolar Transistors ◽

Integrated Circuit ◽

High Speed ◽

Room Temperature ◽

Strain Relaxation ◽

Bipolar Transistors ◽

Sige Hbt ◽

Integrated Circuit Manufacturing ◽

Microstructural Behavior

SiGe is being extensively investigated for use in heterojunction bipolar-transistors (HBT) and high-speed integrated circuits. The material offers adjustable bandgaps, improved carrier mobilities over Si homostructures, and compatibility with Si-based integrated-circuit manufacturing. SiGe HBT performance can be improved by increasing the base-doping or by widening the base link-region by ion implantation. A problem that arises however is that implantation can enhance strain-relaxation of SiGe/Si.Furthermore, once misfit or threading dislocations result, the defects can give rise to recombination-generation in depletion regions of semiconductor devices. It is of relevance therefore to study the damage and anneal behavior of implanted SiGe layers. The present study investigates the microstructural behavior of phosphorus implanted pseudomorphic metastable Si0.88Ge0.12 films on silicon, exposed to various anneals.Metastable pseudomorphic Si0.88Ge0.12 films were grown ~265 nm thick on a silicon wafer by molecular-beam epitaxy. Pieces of this wafer were then implanted at room temperature with 100 keV phosphorus ions to a dose of 1.5×1015 cm-2.

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Polymeric antibacterial systems based on passive targeting and synergistic effect

10.32657/10356/144899 ◽

2020 ◽

Author(s):

◽

Jielin Ma

Keyword(s):

Synergistic Effect ◽

Passive Targeting

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Characteristics Of The Structure Formation Of Gypsum Binder Modified With Zinc Hydrosilicates

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2020.02.40-46 ◽

2020 ◽

pp. 40-46

Keyword(s):

Synergistic Effect ◽

Physicochemical Properties ◽

Structure Formation ◽

Silicic Acid ◽

Chemical Properties ◽

Crystal Formation ◽

Ability To Act ◽

Chemical Factors ◽

Sorption Characteristics

The authors' methodic for assessing the role of chemical and physic-chemical factors during the structure formation of gypsum stone is presented in the article. The methodic is also makes it possible to reveal the synergistic effect and to determine the ranges of variation of controls factors that ensure maximum values of such effect. The effect of a micro-sized modifier based on zinc hydro-silicates on the structure formation of building gypsum is analyzed and corresponding dependencies are found. It is shown that effects of influence of modifier on the properties of gypsum compositions are determined by chemical properties of modifier. Among the mentioned properties are sorption characteristics (which depend on the amount of silicic acid and its state) and physicochemical properties - the ability to act as a substrate during crystal formation. The proposed method can also be extended to other binding substances and materials. This article contributes to the understanding of the processes that occur during the structure formation of composites, which will make it possible to control the structure formation in the future, obtaining materials with a given set of properties.

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