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Recent Advancements in the Applications of ZnO
Published in Shilpi Birla, Neha Singh, Neeraj Kumar Shukla, Nanotechnology, 2022
Chandra Prakash Gupta, Amit Kumar Singh
These are categorized as chemical vapor deposition (CVD) and physical vapor deposition (PVD). Vapors of depositing species undergo chemical reaction at the target surface for thin film deposition by CVD, whereas PVD deposits the thin film by condensing the atoms and molecules in the vapor. CVD encompasses the thermal CVD, atomic layer deposition (ALD), metal-organic CVD (MOCVD), plasma-enhanced CVD (PECVD), low-pressure CVD (LPCVD), laser CVD (LCVD) and molecular-beam epitaxy (MBE).
Materials
Published in Sumit Sharma, Composite Materials, 2021
This fiber was first introduced by Talley in 1959 [1]. In commercial production of boron fibers, the method of chemical vapor deposition (CVD) is used. CVD is a process in which one material is deposited onto a substrate to produce near theoretical density and small grain size for the deposited material. In CVD, the material is deposited on a thin filament. The material grows on this substrate and produces a thicker filament. The size of the final filament is such that it could not be produced by drawing or other conventional methods of producing fibers. It is the fine and dense structure of the deposited material, which determines the strength and modulus of the fiber. In the fabrication of boron fiber by CVD, the boron trichloride is mixed with hydrogen and boron is deposited according to the reaction: 2BCl3(g)+3H2(g)→2B(s)+6HCl(g).
Nanosensor Laboratory
Published in Vinod Kumar Khanna, Nanosensors, 2021
In the broadest sense, CVD involves the formation of a thin solid film on a substrate material by a chemical reaction of vapor-phase precursors. How do you distinguish it from PVD processes, such as evaporation and reactive sputtering?
A critical overview of thin films coating technologies for energy applications
Published in Cogent Engineering, 2023
Mohammad Istiaque Hossain, Said Mansour
Chemical vapor deposition (CVD) technique is an essential system to grow crystalline semiconducting materials under vacuum to develop different devices (Mittal et al., 2021). In general, chemical reaction takes places in the presence of a mediator gas between two different materials to produce active and homogeneous thin films on substrates. The significant part of CVD is that it allows multidirectional depositional rather than a linear type like PVD. This tool allows users to grow materials in various forms, including monocrystalline, polycrystalline, amorphous, and epitaxial. The main working principle allows chemical reaction between a blend of gases and the bulk surface of the material, which causes chemical breakdown of some of the specific gas constituents, forming a thin coating on substrates. CVD has been utilized heavily in many industries to develop semiconducting, dielectric films for various applications (Hoang et al., 2021; Huang et al., 2021; Kalita & Umeno, 2022; Konar & Nessim, 2022; Presti et al., 2022). Some CVD techniques are atmospheric pressure CVD, low-pressure CVD, ultrahigh vacuum CVD, plasma-enhanced CVD, microwave plasma-assisted hot filament CVD, metal-organic CVD, and photo-initiated CVD.
Recent advances and challenges associated with thin film coatings of cutting tools: a critical review
Published in Transactions of the IMF, 2023
A. Aditharajan, N. Radhika, B. Saleh
CVD is extensively used for fabricating diamond and DLC coatings as they cannot be fabricated using PVD effectively. Tribological properties of DLC and diamond coatings garnered more attention from researchers as DLC and diamond coatings reduce the coefficient of friction significantly. So DLC, Al2O3 became an alternative for nitrides and oxides of Ti, Nb, Zr based thin films. The hot filament CVD (HF-CVD) technique is a widely used deposition method to coat diamond and DLC. Adjusting the flow rate of reactive gases used in HFCVD led to a reduction in bonding strength and growth rate while increasing the deposition of a substantial quantity of non-diamond like carbon.53 Pre-working the substrate by seeding diamond increased the quality and provided a cubic structure with high bonding strength.54 One of the significant drawbacks of HFCVD is the build-up of residual stresses, limiting its application to coating thin films as an increase in thickness results in delamination. To overcome this effect, a plasma enhanced CVD system is used to fabricate thick coatings, as the use of plasma reduces the operating temperature and leads to smooth coatings.55
Virtual metrology as an approach for product quality estimation in Industry 4.0: a systematic review and integrative conceptual framework
Published in International Journal of Production Research, 2022
Paul-Arthur Dreyfus, Foivos Psarommatis, Gokan May, Dimitris Kiritsis
The second most studied operation is CVD, along with its variant PECVD. Notably, most papers have not explicitly described the exact industrial operations involved, and thus, they remain vague. PECVD is an exception and is usually differentiated from CVD, although no clear differences exist between the algorithms used for both techniques. CVD is used to produce thin-films, either for adding a new layer or for doping an existing one. As with plasma-etching, great effort is expended to diminish the feature space size, with an emphasis on feature extraction algorithms. In terms of the quality estimator, a 2014 review on VM for CVD explained that the use of SVR is optimal for this application (Purwins et al. 2014). Since then, kernel methods have become the most used methods, among which GPR is the most popular. As GPR is not a scalable algorithm, its rise can be explained by the development of feature extraction algorithms. In terms of VM technical applications, very few papers have focused on machine control (Lin, Hsu, and Yu 2014) for CVD. Because it enhances VM’s impact on the shop floor, it can only be beneficial for implementing CVD control, which motivates further research. Conversely, the implementation of essential group components is an active topic for CVD research. The most used approaches are MW for updatability, diverse DD methods, and SDS, demonstrating the clear presence of concept drift in this industrial application.