Author: Seon-Mee ChoPublisher:
ISBN:
Category :
Languages : en
Pages : 488
Book Description
The Structure and Physical Properties of Microcrystalline Silicon Germanium Alloys and Intrinsic Microcrystalline Silicon Thin Films by Reactive Magnetron Sputtering
Author: Seon-Mee ChoSilicon, Germanium, and Their Alloys
Author: Gudrun KissingerPublisher: CRC Press
ISBN: 1466586656
Category : Science
Languages : en
Pages : 424
Book Description
Despite the vast knowledge accumulated on silicon, germanium, and their alloys, these materials still demand research, eminently in view of the improvement of knowledge on silicon-germanium alloys and the potentialities of silicon as a substrate for high-efficiency solar cells and for compound semiconductors and the ongoing development of nanodevic
Properties of Hydrogenated Amorphous Silicon-germanium Alloys Deposited by Dual Target Reactive Magnetron Sputtering
Author: Samuel J. LevangPublisher:
ISBN:
Category : Silicon alloys
Languages : en
Pages : 36
Book Description
Hydrogenated amorphous silicon-germanium alloy thin films (a-Si1-xGex:H) were deposited using reactive magnetron sputtering. Dual targets of silicon and germanium were sputtered in an argon + hydrogen atmosphere using RF excitation. Films with x = 0.4 were deposited as a function of substrate temperature and hydrogen partial pressure, and were evaluated by dark and photoconductivity, infrared absorption, and optical transmission. Photosensitivity reached a maximum value of about 4500 between 150 and 200°C. Using the stretching modes in the region of 2000 cm-1, the hydrogen bonding was characterized in terms of the preferential attachment ratio (PA), which represents the ratio between H bonded to Si and H bonded to Ge. The PA shows a systematic increase with increasing temperature, generally independent of hydrogen partial pressure. The interplay between thermodynamic and kinetics effects in determining PA and film quality is discussed.
Physical Properties of HWCVD Microcrystalline Silicon Thin Films
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 7
Book Description
This conference paper describes Microcrystalline silicon films were grown with different thicknesses and different hydrogen dilution ratios on glass and Si substrates. Some films were deposited with a seed layer, whereas others were deposited directly on the substrate. We used atomic force microscopy, scanning electron microscopy, and X-ray diffraction to study the morphology and crystalline structure of the samples. We did not find a significant influence of the different substrates on the morphology or crystalline structure. The presence of the seed layer enhanced the crystallization process, decreasing the amount of amorphous layer present in the films. The microstructure of most films was formed by grains, with a subgrain structure. Films grown with low values of dilution ratio had (220) texture and elongated grains, whereas films deposited with high values of dilution ratio were randomly oriented and had an irregular shape.
Heteroepitaxial Growth of Silicon and Germanium Thin Films on Flexible Metal Substrate by Magnetron Sputtering
Author: Renjie WangPublisher:
ISBN:
Category : Epitaxy
Languages : en
Pages :
Book Description
High mobility single-crystalline-like Ge thin films have been demonstrated on inexpensive polycrystalline metallic substrates buffered with oxide buffer layer. Doped films of p-type and n-type were fabricated using radio frequency magnetron sputtering on flexible epitaxial templates produced by ion beam assisted deposition (IBAD). Ideal conditions for fabricating p-type and n-type Ge thin films have been optimized based on their structure and Hall mobility. As defect density in Ge is directly related to the CeO2 buffer, the effect of CeO2 layer thickness and quality has been evaluated. A structural design of a p-i-n junction is proposed for solar cells on our flexible substrate based on electrical and crystal properties of Si and Ge thin films fabricated. In order to achieve an efficient harvesting of photo-generated free carriers, fabrication of substrates terminated with epitaxial conductive layers is studied.
Advanced Strategies in Thin Film Engineering by Magnetron Sputtering
Author: Alberto Palmero Publisher: MDPI
ISBN: 3039364294
Category : Science
Languages : en
Pages : 148
Book Description
Recent years have witnessed the flourishing of numerous novel strategies based on the magnetron sputtering technique aimed at the advanced engineering of thin films, such as HiPIMS, combined vacuum processes, the implementation of complex precursor gases or the inclusion of particle guns in the reactor, among others. At the forefront of these approaches, investigations focused on nanostructured coatings appear today as one of the priorities in many scientific and technological communities: The science behind them appears in most of the cases as a "terra incognita", fascinating both the fundamentalist, who imagines new concepts, and the experimenter, who is able to create and study new films with as of yet unprecedented performances. These scientific and technological challenges, along with the existence of numerous scientific issues that have yet to be clarified in classical magnetron sputtering depositions (e.g., process control and stability, nanostructuration mechanisms, connection between film morphology and properties or upscaling procedures from the laboratory to industrial scales) have motivated us to edit a specialized volume containing the state-of-the art that put together these innovative fundamental and applied research topics. These include, but are not limited to: • Nanostructure-related properties; • Atomistic processes during film growth; • Process control, process stability, and in situ diagnostics; • Fundamentals and applications of HiPIMS; • Thin film nanostructuration phenomena; • Tribological, anticorrosion, and mechanical properties; • Combined procedures based on the magnetron sputtering technique; • Industrial applications; • Devices.
Phase Transformation and Properties of Magnetron Co-Sputtered Gesi Thin Films
Author: Ziwen XuPublisher: Open Dissertation Press
ISBN: 9781374662131
Category :
Languages : en
Pages :
Book Description
This dissertation, "Phase Transformation and Properties of Magnetron Co-sputtered GeSi Thin Films" by Ziwen, Xu, 徐子文, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. DOI: 10.5353/th_b3984877 Subjects: Sputtering (Physics) Thin films Germanium Silicon Magnetrons
Structure of Amorphous Silicon and Germanium Alloy Films
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The primary objective of the research is to improve the understanding at the microscopic level of amorphous silicon and germanium film structures deposited under various methods. The work is to correlate and theoretically analyze, nuclear magnetic resonance, NMR, ESR, electron spin resonance, and other measurements. The alloys of concern include those obtained by adding dopants to hydrogenated silicon and germanium. The work has been directed to continue deuteron magnetic resonance DMR studies and to pay particulate attention to those structural features which may correlate with the photoelectronic properties of the material. The 1990 (DMR) accomplishments have included correlation of inhomogeneous nuclear spin relaxation with photovoltaic quality. In a second project, a structural rearrangement of atoms has been demonstrated to be associated with the light-induced metastability in a-Si:D, H films. A third approach has employed proton-deuteron coupled spin dynamics to examine hydrogen and deuterium motions in quality films of a-Si:H; a-Si:P, H; and a-Si:D, H. The B- P-doped films show a significantly enhanced hydrogen mobility above 200 K. We also have performed a number of detailed calculations on the effects coordination and strain on the deep electronic states rising from B and P dopants in a-Si as well as the band tail states in the gap of a-Si arising from strained bonds. This work gives a rather complete picture of the effects on the gap states of strain and dopants in the absence of H and for a given configuration of the a-Si network. We conclude that the methods that we have developed over the past three years are capable of describing many of the effects of strained bonds, especially their effect on dopants. 25 refs., 11 figs., 3 tabs.
Preparation and Strength Properties of Germanium-silicon Alloys
Author: Thomas W. GibbsKinetic Studies of Growth of Silicon and Silicon Germanium Thin Films: Gas-surface Reactivity, Germanium Surface Segregation, and the Effect of Coincident Atomic Hydrogen
Author: Yongjun ZhengPublisher:
ISBN: 9780599831490
Category :
Languages : en
Pages : 275
Book Description
Based on the kinetic studies presented in this thesis, a novel process was proposed to achieve selective epitaxial growth of Si and Si1-x Gex. Preliminary results show that up to 300 nm epitaxial silicon has been grown while with no sign of polycrystalline silicon growth.