Photoluminescence and Photoluminescence Excitation Spectroscopy of Cu(In,Ga)Se2 Thin Films

2009 ◽  
Vol 1165 ◽  
Author(s):  
Damon N. Hebert ◽  
Julio A. N. T. Soares ◽  
Angus A. Rockett
Keyword(s):  
Thin Films ◽  
Radiative Recombination ◽  
High Efficiency ◽  
Photoluminescence Excitation ◽  
Defect States ◽  
Band Tail ◽  
Shallow Defect ◽  
Shallow State

AbstractThe role of intrinsic point defects on radiative recombination in Cu(In,Ga)Se2 thin films was investigated by photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopies. Experiments were performed on device-grade polycrystalline layers and single crystal thin films. PL transitions identified by others as indicating a shallow state with an ionization energy of ∼16 meV is proposed to be a transition into band tail states rather than a distinct shallow defect. The presence of deep levels contributing to radiative recombination does not necessarily preclude the material from producing a high efficiency device and may suggest the absence of dominant non-radiative recombination pathways. The band edge width as measured by PLE and the separation of this edge from defect states are suggested to be potentially effective indicators of the quality of a material. Luminescence that appears to be connected with the absence of Na in the growth process persists in high Ga alloy, Na containing materials, suggesting that Na may become ineffective in passivating or eliminating certain defects in high Ga material.

Radiative Recombination in the Cu(In,Ga)Se2 Thin Films Irradiated with Hydrogen Ions

2019 ◽  
Vol 18 (03n04) ◽  
pp. 1940033
Author(s):  
O. Borodavchenko ◽  
V. Zhivulko ◽  
M. Yakushev ◽  
M. Sulimov
Keyword(s):  
Thin Films ◽  
Low Temperature ◽  
Solid Solutions ◽  
Radiative Recombination ◽  
Energy Levels ◽  
Hydrogen Ions ◽  
Photoluminescence Excitation ◽  
Photoluminescence Spectra ◽  
Induced Defects ◽  
Irradiation Induced Defects

The irradiation-induced effects in Cu(In,Ca)Se2 thin films after irradiation with hydrogen ions with dose of [Formula: see text][Formula: see text]cm[Formula: see text] and different energies in the range of 2.5–10[Formula: see text]keV were studied. Irradiated and nonirradiated thin films were investigated by low-temperature (4.2[Formula: see text]K) photoluminescence and photoluminescence excitation methods. The appearance of intense bands at [Formula: see text][Formula: see text]eV and 0.77[Formula: see text]eV in the photoluminescence spectra may be related to radiative recombination on the irradiation-induced defects with deep energy levels in the bandgap of Cu(In,Ca)Se2 solid solutions. A possible nature of these defects and process of radiative recombination are discussed.

High-Quality A-Si Films Prepared by the Direct Photo-Cvd Method

1989 ◽  
Vol 149 ◽  
Author(s):  
S. Nakano ◽  
K. Wakisaka ◽  
M. Kameda ◽  
M. Isomura ◽  
T. Matsuyama ◽  
...  
Keyword(s):  
High Efficiency ◽  
Defect States ◽  
Low Light ◽  
High Quality ◽  
Characteristic Energy ◽  
Area Efficiency ◽  
Cvd Method ◽  
Si Solar Cell ◽  
Si Films

ABSTRACTA high-efficiency integrated-type a-Si solar cell submodule with a size of 10cm × 10cm has been fabricated and a total area efficiency of 9.6% is obtained by using a high-quality p-layer doped with B(CH3)3 We have developed an advanced direct photo-CVD method. High-quallt” a-SI films with low tail characteristic energy and low light-induced degradation is prepared by this method. We have also studied the role of Si-H2 bonds on the light-induced effect. The result implies that Si-H bonds stabilize the defect states, resulting in a large light-induced degradation.

The Peculiar Role of the Third Element Indium in Density of Defect States of Se90Ge10 Thin Films

2017 ◽  
Vol 6 (4) ◽  
pp. 424-427
Author(s):  
R. Mishra ◽  
Anjani Kumar ◽  
D. Kumar ◽  
S. Shukla ◽  
R. K. Shukla
Keyword(s):  
Thin Films ◽  
Defect States ◽  
The Third ◽  
Density Of Defect States

Role of defect states on electrical and optical properties in CdSe nanorod thin films

2008 ◽  
Vol 40 (6) ◽  
pp. 2063-2065 ◽  
Author(s):  
A. Cretì ◽  
G. Leo ◽  
A. Persano ◽  
A. Cola ◽  
L. Manna ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Defect States ◽  
Electrical And Optical Properties ◽  
Cdse Nanorod

scholarly journals When machines think for us: the consequences for work and place

2020 ◽  
Vol 13 (1) ◽  
pp. 3-23 ◽  
Author(s):  
Judith Clifton ◽  
Amy Glasmeier ◽  
Mia Gray
Keyword(s):  
High Efficiency ◽  
Business Culture ◽  
Education Levels ◽  
And Gender ◽  
The Relationship ◽  
Culture Education ◽  
Direct Use ◽  
Displacement Effects

Abstract The relationship between technology and work, and concerns about the displacement effects of technology and the organisation of work, have a long history. The last decade has seen the proliferation of academic papers, consultancy reports and news articles about the possible effects of Artificial Intelligence (AI) on work—creating visions of both utopian and dystopian workplace futures. AI has the potential to transform the demand for labour, the nature of work and operational infrastructure by solving complex problems with high efficiency and speed. However, despite hundreds of reports and studies, AI remains an enigma, a newly emerging technology, and its rate of adoption and implications for the structure of work are still only beginning to be understood. The current anxiety about labour displacement anticipates the growth and direct use of AI. Yet, in many ways, at present AI is likely being overestimated in terms of impact. Still, an increasing body of research argues the consequences for work will be highly uneven and depend on a range of factors, including place, economic activity, business culture, education levels and gender, among others. We appraise the history and the blurry boundaries around the definitions of AI. We explore the debates around the extent of job augmentation, substitution, destruction and displacement by examining the empirical basis of claims, rather than mere projections. Explorations of corporate reactions to the prospects of AI penetration, and the role of consultancies in prodding firms to embrace the technology, represent another perspective onto our inquiry. We conclude by exploring the impacts of AI changes in the quantity and quality of labour on a range of social, geographic and governmental outcomes.

Anti-solvent dependent device performance in CH3NH3PbI3 solar cells: the role of intermediate phase content in the as-prepared thin films

2017 ◽  
Vol 1 (5) ◽  
pp. 1041-1048 ◽  
Author(s):  
Yang Li ◽  
Jianan Wang ◽  
Yi Yuan ◽  
Xiandui Dong ◽  
Peng Wang
Keyword(s):  
Thin Films ◽  
Solar Cells ◽  
Intermediate Phase ◽  
Device Performance ◽  
Phase Content ◽  
Solution Processed ◽  
Inorganic Hybrid

Our work highlights the intrinsic role of an intermediate phase in controlling the film quality of a solution processed organic–inorganic hybrid CH3NH3PbI3.

scholarly journals The role of oxytocin in the pathogenesis of endometriosis: various aspects of the problem

2019 ◽  
Vol 68 (3) ◽  
pp. 89-98 ◽  
Author(s):  
Maria I. Yarmolinskaya ◽  
Vladislav V. Khobets
Keyword(s):  
Quality Of Life ◽  
Affective Disorders ◽  
Chronic Pelvic Pain ◽  
High Efficiency ◽  
Recurrent Disease ◽  
Medical Condition ◽  
Oxytocin Receptor ◽  
Degrees Of Severity

Hypothesis/aims of study. Endometriosis is a chronic recurrent disease that leads to a significant decrease in the quality of life. Despite the existing therapeutic methods, the prevalence of the disease is steadily increasing. The pathogenesis of endometriosis has not been studied enough, resulting in failure to achieve high efficiency in its treatment. Due to chronic pelvic pain, infertility, and dissatisfaction with the quality of life, women suffering from endometriosis present with various mental disorders of different degrees of severity. This study aims to summarize the literature discussing the possible role of oxytocin in the pathogenesis of both endometriosis and affective disorders. Study design, materials, and methods. Literature data for the period from 1986 to 2019. Conclusion. The role of oxytocin in the pathogenesis of endometriosis needs further study. Oxytocin receptor antagonists can be considered promising in the treatment of this medical condition, as well as in prevention and management of affective disorders in patients with endometriosis.

Surface-reduced Si-doped TiO2 nanotubes for high-efficiency photoelectrochemical water splitting

2019 ◽  
Vol 12 (06) ◽  
pp. 1940004
Author(s):  
Dawei Si ◽  
Zhenbiao Dong ◽  
Ting Li ◽  
Dongyan Ding ◽  
Congqin Ning
Keyword(s):  
Water Splitting ◽  
High Efficiency ◽  
Photocurrent Density ◽  
Reduction Reaction ◽  
Photoelectrochemical Water Splitting ◽  
Defect States ◽  
Photogenerated Electrons ◽  
Long Time ◽  
Si Doped

TiO2 is a promising photocatalyst in the reaction of water splitting for hydrogen. Here, we used NaBH4 reduction reaction to introduce [Formula: see text]/VO defect states into Si-doped TiO2 nanotubes and investigated the photoelectrochemical water splitting properties. It was found that the photocatalytic activity was improved through NaBH4 reduction because of the existence of [Formula: see text]/VO. The defect states ([Formula: see text]/VO) could play a role of capture trap and accelerate the separation of photogenerated electrons and holes. The photocurrent density of the Si-doped TiO2 nanotubes reduced for 3[Formula: see text]h was 1.5[Formula: see text]mA/cm2 compared to 0.7[Formula: see text]mA/cm2 of the unreduced nanotubes. The conversion efficiency was 0.7%, which was almost 4 times than that of pure TiO2. On the other hand, reduction for a long time would generate excess defect states and thus cause the decrease of photocurrent density. Excess defect states could act as the recombination centers of photogenerated electrons and holes.

scholarly journals SITUATIONAL TASKS AS AN EFFECTIVE TOOL OF KNOWLEDGE CONTROL OF HIGHER EDUCATION’S APPLICANTS

2021 ◽  
pp. 244-247
Author(s):  
T. YARNYKH ◽  
O. RUKHMAKOVA ◽  
N. ORLOVETSKA
Keyword(s):  
Higher Education ◽  
Professional Training ◽  
High Efficiency ◽  
Educational Institution ◽  
Cognitive Activity ◽  
Educational Process ◽  
Self Control ◽  
High Level

The organization of the educational process in a higher educational institution must meet the world standards of higher education, provide active motivation for higher education’s applicants to obtain professional knowledge and guarantee quality education. The modern process of professional training in Ukraine is carried out under the influence of the requirements of the European educational space. Higher School of Pharmacy is dynamically developing and constantly changing, improving the quality of specialists with higher pharmaceutical education, which is provided by improving educational programs in each discipline and a new approach to their teaching. The article considers the role of situational tasks as an effective tool for monitoring the knowledge of higher education’s applicants. It is shown that the method of knowledge control using situational tasks encourages higher education’s applicants to study not only basic but also additional educational literature, to improve methods of self-control of knowledge and skills. Situational tasks are one of the means to achieve high efficiency of educational activities of higher education’s applicants in the development of certain competencies through various types of vocational education. They are especially important in distance education, as they provide a high level of independence and creativity in the cognitive activity of higher education.

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