The Boron-Oxygen Defect: Does its Concentration Really Depends on the Boron/Dopant Concentration?

Author(s):  
Fiacre Rougieux ◽  
Chang Sun ◽  
Mattias Juhl
1988 ◽  
Vol 100 ◽  
Author(s):  
Michael P. Siegal ◽  
Jorge J. Santiago

ABSTRACTSecondary ion mass spectroscopy has been used to study the effects of rapid thermal processing on the formation of tetragonal tungsten disilicide thin films on Si(100), p-type 5 Omaga;, cm wafers. The substrates were chemically etched, followed by an RF sputter depostion of 710Å W metal. The samples were then fast radiatively processed in an RTP system for time intervals ranging from 15 to 45 seconds at high temperature (∼1100°C) under high vacuum.The redistribution of the boron dopant concentration profile is studied and shows that boron moves from the Si-substrate into the growing Wsi2 film, eventually escaping into the vacuum. Oxygen is the major impurity in these samples and its removal from the interface has been shown to improve the quality of the silicide film. Trace quantities of F, Cl, Na, K, C and Cr have also been detected.


1981 ◽  
Vol 4 ◽  
Author(s):  
C Hill ◽  
A L Butler ◽  
J A Daly

ABSTRACTOver the past ten years, the performance of bipolar transistors in high speed integrated circuits has been steadily improved by fully exploiting the complex solid state diffusion behaviour of dopants in silicon to make successively closer approaches to the ideal dopant profiles in the emitter and base regions of the transistor. Further optimisation requires a new approach, and in this paper an entirely new method of shaping the dopant profiles by exploiting the large ratio (about 108) of diffusion coefficients in liquid and solid silicon near the melting point is described Melting is effected by irradiation with a homogenised pulse from a Q-switched ruby laser. Completely new features of the technique are the controllable fabrication of both quasi–Gaussian and quasi-rectangular dopant profiles independent of dopant (arsenic or boron), dopant concentration (1013−1016atom cm−2) or presence of other dopants. This allows for the first time independent optimisation of emitter profile shape, emitter doping level, and base profile in bipolar transistor structures.


Author(s):  
Tsan-Chang Chuang ◽  
Cha-Ming Shen ◽  
Shi-Chen Lin ◽  
Chen-May Huang ◽  
Jin-Hong Chou ◽  
...  

Abstract Scanning capacitance microscopy (SCM) is a 2-D carrier and/or dopant concentration profiling technique under development that utilizes the excellent spatial resolution of scanning probe microscopy. However, PV-SCM has limited capability to achieve the goal due to inherent "plane" trait. On top of that, deeper concentration profile just like deep N-well is also one of restrictions to use. For representing above contents more clearly, this paper presents a few cases that demonstrate the alternated and optimized application of PV-SCM and X-SCM. The case studies concern Joint Test Action Group failure and stand-by failure. These cases illustrate that the correct selection from either plane-view or cross-sectional SCM analysis according to the surrounding of defect could help to exactly and rapidly diagnose the failure mechanism. Alternating and optimizing PV-SCM and X-SCM techniques to navigate various implant issue could provide corrective actions that suit local circumstance of defects and identify the root cause.


Author(s):  
Atefeh Nazari Setayesh ◽  
Hassan Sedghi

Background: In this work, CdS thin films were synthesized by sol-gel method (spin coating technique) on glass substrates to investigate the optical behavior of the film. Methods: Different substrate spin coating speeds of 2400, 3000, 3600 rpm and different Ni dopant concentrations of 0 wt.%, 2.5 wt.%, 5 wt.%) were investigated. The optical properties of thin films such as refraction index, extinction coefficient, dielectric constant and optical band gap energy of the layers were discussed using spectroscopic ellipsometry method in the wavelength range of 300 to 900 nm. Results: It can be deduced that substrate rotation speed and dopant concentration has influenced the optical properties of thin films. By decreasing rotation speed of the substrate which results in films with more thicknesses, more optical interferences were appeared in the results. Conclusion: The samples doped with Ni comparing to pure ones have had more optical band gap energy.


Nano Energy ◽  
2021 ◽  
pp. 106164
Author(s):  
Xinyue Liang ◽  
Lijin Yan ◽  
Wenpo Li ◽  
Youcun Bai ◽  
Chong Zhu ◽  
...  
Keyword(s):  

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1118
Author(s):  
Ibrahim Mustapha Alibe ◽  
Khamirul Amin Matori ◽  
Mohd Hafiz Mohd Zaid ◽  
Salisu Nasir ◽  
Ali Mustapha Alibe ◽  
...  

The contemporary market needs for enhanced solid–state lighting devices has led to an increased demand for the production of willemite based phosphors using low-cost techniques. In this study, Ce3+ doped willemite nanoparticles were fabricated using polymer thermal treatment method. The special effects of the calcination temperatures and the dopant concentration on the structural and optical properties of the material were thoroughly studied. The XRD analysis of the samples treated at 900 °C revealed the development and or materialization of the willemite phase. The increase in the dopant concentration causes an expansion of the lattice owing to the replacement of larger Ce3+ ions for smaller Zn2+ ions. Based on the FESEM and TEM micrographs, the nanoparticles size increases with the increase in the cerium ions. The mean particles sizes were estimated to be 23.61 nm at 1 mol% to 34.02 nm at 5 mol% of the cerium dopant. The optical band gap energy of the doped samples formed at 900 °C decreased precisely by 0.21 eV (i.e., 5.21 to 5.00 eV). The PL analysis of the doped samples exhibits a strong emission at 400 nm which is ascribed to the transition of an electron from localized Ce2f state to the valence band of O2p. The energy level of the Ce3+ ions affects the willemite crystal lattice, thus causing a decrease in the intensity of the green emission at 530 nm and the blue emission at 485 nm. The wide optical band gap energy of the willemite produced is expected to pave the way for exciting innovations in solid–state lighting applications.


RSC Advances ◽  
2021 ◽  
Vol 11 (13) ◽  
pp. 7338-7346
Author(s):  
Sunjae Kim ◽  
Heejoong Ryou ◽  
In Gyu Lee ◽  
Myunghun Shin ◽  
Byung Jin Cho ◽  
...  

The photocatalytic activity is correlated with different parameters affecting the photocatalytic reactions; redox potential (RP), surface area (SA), crystal defect (CD), oxygen defect (OD), and grain-boundary induced defect (GD).


Crystals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 458
Author(s):  
Nikolay V. Sidorov ◽  
Natalia A. Teplyakova ◽  
Olga V. Makarova ◽  
Mikhail N. Palatnikov ◽  
Roman A. Titov ◽  
...  

Defect structure of nominally pure lithium niobate crystals grown from a boron doped charge have been studied by Raman and optical spectroscopy, laser conoscopy, and photoinduced light scattering. An influence of boron dopant on optical uniformity, photoelectrical fields values, and band gap have been also studied by these methods in LiNbO3 crystals. Despite a high concentration of boron in the charge (up to 2 mol%), content in the crystal does not exceed 10−4 wt%. We have calculated that boron incorporates only into tetrahedral voids of crystal structure as a part of groups [BO3]3−, which changes O–O bonds lengths in O6 octahedra. At this oxygen–metal clusters MeO6 (Me: Li, Nb) change their polarizability. The clusters determine optically nonlinear and ferroelectric properties of a crystal. Chemical interactions in the system Li2O–Nb2O5–B2O3 have been considered. Boron, being an active element, structures lithium niobate melt, which significantly influences defect structure and physical properties of a crystal grown from such a melt. At the same time, amount of defects NbLi and concentration of OH groups in LiNbO3:B is close to that in stoichiometric crystals; photorefractive effect, optical, and compositional uniformity on the contrary is higher.


1999 ◽  
Vol 14 (1) ◽  
pp. 90-96 ◽  
Author(s):  
R. Ramamoorthy ◽  
S. Ramasamy ◽  
D. Sundararaman

Nanocrystalline zirconia powders in pure form and doped with yttria and calcia were prepared by the precipitation method. In the as-prepared condition, all the doped samples show only monoclinic phase, independent of the dopants and dopant concentration. On annealing the powders at 400 °C and above, in the case of 3 and 6 mol% Y2O3 stabilized ZrO2 (3YSZ and 6YSZ), the monoclinic phase transforms to tetragonal and cubic phases, respectively, whereas in 3 and 6 mol% CaO stabilized ZrO2 (3CSZ and 6CSZ), the volume percentage of the monoclinic phase gradually decreases up to the annealing temperature of about 1000 °C and then increases for higher annealing temperatures. The presence of monoclinic phase in the as-prepared samples of doped zirconia has been attributed to the lattice strain effect which results in the less symmetric lattice. For the annealing temperatures below 1000 °C, the phenomenon of partial stabilization of the tetragonal phase in 3CSZ and 6CSZ can be explained in terms of the grain size effect. High resolution transmission electron microscopy (HRTEM) observations reveal the lattice strain structure in the as-prepared materials. The particles are found to be a tightly bound aggregate of small crystallites with average size of 10 nm. The morphology of the particles is observed to be dependent on the dopants and dopant concentration.


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