An Optical Approach to Evaluating the Effects of Chlorine on the Quality Of Si/SiO2 Interfaces

1996 ◽  
Vol 428 ◽  
Author(s):  
Julia Sherry ◽  
John Lowell ◽  
Tim Hossain ◽  
Damon Debusk
Keyword(s):  
Alkali Metals ◽  
Contact Potential Difference ◽  
Environmental Concerns ◽  
Device Performance ◽  
Optical Surface ◽  
Contact Potential ◽  
High Injection ◽  
Injection Frequency ◽  
P Type

AbstractIn CMOS, the addition of chlorine particularly in TCA form to the growth of thermal oxides in logic technologies is well-known and pervasive. In addition to the increasing environmental concerns of chlorine use, one of the important parameters is the amount of metallic contamination due to transition metals such as Fe in the Si, and alkali metals like Na in the oxide since these phenomena effect both device performance and quality. However, the ability to measure this parameter on product material is not generally available due to inherent problems with most known methods. In this paper we report on the application of high-injection, frequency based optical surface photovoltage (SPV) and a more recent technique known as a contact potential difference (CPD) to both quantify and qualify as-grown oxides on CZ P-type silicon.

Measuring Diffusion Lengths in Epitaxial Silicon by Surface Photovoltage

1995 ◽  
Vol 386 ◽  
Author(s):  
John Lowell ◽  
Valerie Wenner ◽  
Damon Debusk
Keyword(s):  
Transition Metals ◽  
Optical Filters ◽  
Surface Photovoltage ◽  
Epitaxial Layers ◽  
Device Performance ◽  
Optical Surface ◽  
Epitaxial Silicon ◽  
Type Silicon ◽  
P Type ◽  
And Diffusion

ABSTRACTIn CMOS, the use of epitaxial layers for prevention of latch-up in logic technologies is well-known and pervasive. One of the crucial parameters is the amount of metallic contamination due to transition metals such as Fe in the epi since this phenomena effects both device performance and quality. However, the ability to measure this parameter on product material is not generally available due to inherent problems with most known methods. The limitation of traditional surface photovoltage is that the deep optical penetration of over a hundred microns is well-beyond the depth of most epitaxial layers and does not accurately profile the epitaxial region [1]. In this paper we report on the application of optical surface photovoltage (SPV) using a set of ultra-shallow optical filters to both quantify and qualify as-grown epitaxial layers on CZ P-type silicon. We believe that a non-contact, SPV measurement of Fe concentration and diffusion lengths within an epitaxial region has not been previously reported.

Contact Potential Difference of ZnO Layer Adsorbing p-Type Dye and n-Type Dye

1979 ◽  
Vol 18 (12) ◽  
pp. 2315-2316 ◽  
Author(s):  
Tetsuzo Yoshimura ◽  
Kohei Kiyota ◽  
Hiroo Ueda ◽  
Masao Tanaka
Keyword(s):  
Contact Potential Difference ◽  
Potential Difference ◽  
Contact Potential ◽  
P Type

scholarly journals Работа выхода электрона углеродных нанокомпозитных пленок по данным вакуумной и атмосферной фотоэмиссии

2020 ◽  
Vol 90 (6) ◽  
pp. 982
Author(s):  
Д.А. Бокизода ◽  
А.Ф. Зацепин ◽  
Е.А. Бунтов ◽  
А.И. Слесарев
Keyword(s):  
Fermi Level ◽  
Work Function ◽  
Ambient Pressure ◽  
Contact Potential Difference ◽  
Electron Work Function ◽  
Silicon Substrates ◽  
Contact Potential ◽  
Carbon Coatings ◽  
Energy Characteristics

The energy characteristics of carbyne-containing films on copper and silicon substrates have been studied using the methods of optically stimulated electron emission (OSEE) and ambient pressure photoemission spectroscopy (APS). The average contact potential difference and the work function were determined, and the positions of the Fermi level for carbonaceous films of various thicknesses were calculated. It was found that the electron work function and the position of the Fermi level of the studied film samples are independent of the film thickness and the type of substrate. The information capabilities of the OSEE and APS methods for assessing the quality of carbon coatings on various substrates are shown.

scholarly journals Coupled Investigation of Contact Potential and Microstructure Evolution of Ultra-Thin AlOx for Crystalline Si Passivation

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1803
Author(s):  
Zhen Zheng ◽  
Junyang An ◽  
Ruiling Gong ◽  
Yuheng Zeng ◽  
Jichun Ye ◽  
...  
Keyword(s):  
Structural Changes ◽  
Silicon Oxide ◽  
Crystalline Silicon ◽  
Contact Potential Difference ◽  
Potential Difference ◽  
Kelvin Probe ◽  
Contact Potential ◽  
Carrier Lifetimes ◽  
Transmission Electron ◽  
Effective Carrier

In this work, we report the same trends for the contact potential difference measured by Kelvin probe force microscopy and the effective carrier lifetime on crystalline silicon (c-Si) wafers passivated by AlOx layers of different thicknesses and submitted to annealing under various conditions. The changes in contact potential difference values and in the effective carrier lifetimes of the wafers are discussed in view of structural changes of the c-Si/SiO2/AlOx interface thanks to high resolution transmission electron microscopy. Indeed, we observed the presence of a crystalline silicon oxide interfacial layer in as-deposited (200 °C) AlOx, and a phase transformation from crystalline to amorphous silicon oxide when they were annealed in vacuum at 300 °C.

scholarly journals Mechanical Properties, Corrosion Resistance and Bioactivity of Oxide Layers Formed by Isothermal Oxidation of Ti-6Al-7Nb Alloy

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 505
Author(s):  
Krzysztof Aniołek ◽  
Bożena Łosiewicz ◽  
Julian Kubisztal ◽  
Patrycja Osak ◽  
Agnieszka Stróż ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Contact Potential Difference ◽  
Isothermal Oxidation ◽  
Potential Method ◽  
Open Circuit ◽  
Kelvin Probe ◽  
Contact Potential ◽  
Oxide Layers

Titanium and its alloys are among the most promising biomaterials for medical applications. In this work, the isothermal oxidation of Ti-6Al-7Nb biomedical alloy towards improving its mechanical properties, corrosion resistance, and bioactivity has been developed. The oxide layers were formed at 600, 700, and 800 °C for 72 h. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), 3D profilometry, and microindentation test, were used to characterize microstructure, surface geometrical structure, and the hardness of the diphase (α + β) Ti-6Al-7Nb alloy after oxidation, respectively. In vitro corrosion resistance tests were carried out in a saline solution at 37 °C using the open-circuit potential method and potentiodynamic measurements. Electronic properties in the air were studied using the Scanning Kelvin Probe (SKP) technique. The bioactivity test was conducted by soaking the alkali- and heat-treated samples in simulated body fluid for 7 days. The presence of apatite was confirmed using SEM/EDS and Fourier Transform Infrared Spectroscopy (FTIR) studies. The thickness of oxide layers formed increased with the temperature growth from 0.25 to 5.48 µm. It was found that with increasing isothermal oxidation temperature, the surface roughness, hardness, corrosion resistance, and contact potential difference increased. The Ti-6Al-7Nb alloy after oxidation revealed the HAp-forming ability in a biological environment.

Efficient All-inorganic Perovskite Light-emitting Diodes Enabled by Manipulating Crystal Orientation

2021 ◽  
Author(s):  
Wenjing Feng ◽  
Kebin Lin ◽  
Wenqiang Li ◽  
Xiangtian Xiao ◽  
Jianxun Lu ◽  
...  
Keyword(s):  
Active Layer ◽  
Crystal Orientation ◽  
Light Emitting Diodes ◽  
Metal Halide ◽  
Device Performance ◽  
Light Emitting ◽  
Inorganic Perovskite ◽  
Metal Halide Perovskite ◽  
Halide Perovskite

Metal halide perovskite light-emitting diodes (PeLEDs) are promising in lighting and display application, and the corresponding device performance is highly dependent on the film quality of the active layer. However,...

Comparative Surface Imaging Study of Multifocal Diffractive Intraocular Lenses

2021 ◽  
Author(s):  
Hyeck Soo Son ◽  
Jung Min Lee ◽  
Ramin Khoramnia ◽  
Chul Young Choi
Keyword(s):  
Imaging Study ◽  
The Other ◽  
Intraocular Lenses ◽  
Optical Surface ◽  
Diffractive Optic ◽  
Atomic Force ◽  
Acceptable Range ◽  
Different Types ◽  
Concentric Pattern

Abstract Purpose To analyse and compare the surface topography and roughness of three different types of diffractive multifocal IOLs. Methods Using scanning electron microscope (SEM, Inspect F, 5.0 KV, maximum magnification up to 20,000) and atomic force microscope (AFM, Park Systems, XE-100, non-contact, area profile comparison, 10 × 10 µm, 40 × 40 µm), the surface quality of the following diffractive IOLs was studied: the AcrySof IQ PanOptix (Alcon, USA), the AT LARA 829MP (Carl Zeiss Meditec, Germany), and Tecnis Symfony (Johnson&Johnson Vision, USA). The measurements were made over three representative areas (central non-diffractive optic, central diffractive optic, and diffractive step) of each IOL. Roughness profile in terms of mean arithmetic roughness (Ra) and root-mean-squared roughness (Rq) values were obtained and compared statistically. Results In SEM examination, all IOLs showed a smooth optical surface without any irregularities at low magnification. At higher magnification, Tecnis Symfony showed unique highly regular, concentric, and lineate structures in the diffractive optic area which could not be seen in the other studied diffractive IOLs. The differences in the measured Ra and Rq values of the Tecnis Symfony were statistically significant compared to the other models (p < 0.05). Conclusion Various different topographical traits were observed in three diffractive multifocal IOLs. The Ra values of all studied IOLs were within an acceptable range. Tecnis Symfony showed statistically significant higher surface Ra values at both central diffractive optic and diffractive step areas. Furthermore, compared to its counterparts, Tecnis Symfony demonstrated highly ordered, concentric pattern in its diffractive surfaces.

Professional Psychology in Portugal

1997 ◽  
Vol 81 (3_suppl) ◽  
pp. 1211-1222 ◽  
Author(s):  
Teresa Fagulha ◽  
Richard H. Dana
Keyword(s):  
Rapid Development ◽  
Well Being ◽  
Professional Psychology ◽  
Current Status ◽  
Environmental Concerns ◽  
Advanced Degrees ◽  
Professional Degree ◽  
History Of ◽  
Training Research

This paper describes the history and current status of professional psychology in Portugal where a unique perspective combines training, research, and practical contributions from Europe and the Americas with their own history of psychological tradition and expertise. Training in professional psychology includes Social Psychology and Educational and Vocational Guidance specializations in addition to Clinical Psychology and Psychotherapy and Counseling for the professional degree, Licenciatura. Advanced degrees are offered in Environmental Psychology, Career Development, Social Cognition, and other areas, primarily for academic positions. Research in all of these areas is expected to have applied outcomes that contribute to individual well being and an improved quality of life for the entire population. The result has been a rapid development of an indigenous professional psychology to address mental health, social, and environmental concerns that compel psychological attention and resources worldwide as well as those problems of local and national origins.

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