Molybdenum Incorporation Induced Enhancement in the Mechanical Properties of Gallium Oxide Films

Abstract

However, in all these applications, fundamental understanding of the physics and chemistry of Ga-oxide-based nanomaterials so as to provide a better control on the interplay between surface/interface structure, thermodynamic conditions, chemical processes, and kinetics is the key to achieving enhanced efficiency as well as control over the environmental pollutants.The mechanical properties of metaloxide nanostructures are quite important for utilizing them in energy related applications, such as absorber layers in concentrated solar power plants and integrated sensors in oxy-combustion as encountered in coal-based power plants. Thus, fundamental knowledge of such nanomaterials' mechanical behavior and the relationship with the microstructure is critical to effectively utilize them in practical applications, where the presence of extreme environments (higher temperature and pressures) is common. Under such conditions, it becomes critical to understand how the structural modifications (if any) affect the other properties, most importantly the mechanical characteristics which determine their survivability. For example, the materials which are used in microelectronics, sensors, and semiconductor devices must perform their function, but they must also meet certain chemical and mechanical properties to be able to function and not to failure easily. [24,25] These devices must be reliable, durable, and must possess structural integrity over their lifetime. Therefore, the material chosen must provide adequate resistance to the mechanical and chemical changes arises in the specific applications during the performance. The mechanical behavior of nanomaterials focuses on the two points at a high rate of loading. Using the materials under specific conditions where the material should sustain to sudden impact loads or temperatures fluctuations is the first. A deeper understanding of the mechanical properties and how the mechanical characteristics depend on different types of applied stresses is most important. Understanding the relation between physical phenomena and molecular structure in view of the variation of the stress-strain diagram with different peak indent loading rates is the later. [24][25][26] Such a detailed understanding will enable the design and development of advanced, high-performance structural materials. [27,28] In this context, for the first time, the present work was focused on using a mechanically resilient metal (Mo) to incorporate into Ga-oxide to provide excellent physical and thermomechanical characteristics, which are essential to utilize the Ga-oxide nanomaterials in energy related device applications. An approach to design Ga 2 O 3 -based nanomaterials with tunable mechanical properties is presented. In the molybdenum (Mo) incorporated Ga 2 O 3 model system, where Mo content (x) is varied up to ≈11 at%, Mo-incorporation induced effects are significant on the structural and mechanical properties. Single-phase β-Ga 2 O 3 formation occurs for lower Mo content (≤4 at%); however, higher Mo content ind...

Nanomechanical and Material Properties of Fluorine-Doped Tin Oxide Thin Films Prepared by Ultrasonic Spray Pyrolysis: Effects of F-Doping

“…The H/Ef values of the FTO thin films are in the range of 0.059–0.093 (Table 2). These H/Ef values are larger than those of the Bi 3 Se 2 Te films (i.e., 0.028–0.031) [29], and reasonably smaller than the H/E > 0.1 values of some brittle materials, such as ceramic Mo-incorporation β -Ga 2 O 3 films [51] and hard nanocomposite coatings with columnar microstructures [52]. In addition, the H3/Ef2 values increased from 0.019 to 0.107 GPa and then decreased to 0.073 GPa due to the variation of the grain size (Table 2).…”

Mechanical Properties of Nanocrystalline and Amorphous Gallium Oxide Thin Films

“…However, nano‐indentation measurements are well known, reliable and provides a simple and quick method for obtaining information about the mechanical properties of thin films . The reproducibility is good, but, when the ratio of indentation depth to the film thickness ( d / t ) exceeds a critical value, then the measured mechanical properties are going to be influenced by the substrate material and it is no longer characteristics of the coating . Therefore, one needs to identify the penetration depth by monitoring the phenomena with respect to indentation load.…”

“…The data obtained for Ga 2 O 3 films (Figure a) indicate that most of the films exhibit H / E r ≤ 0.1. Note that the Ga 2 O 3 films deposited are ceramics; therefore, H / E r ratio is expected to be less than 0.1 . The H / E r ratio for the nano‐crystalline Ga 2 O 3 films is 0.085 ± 0.05 and almost constant.…”

“…[37] The reproducibility is good, but, when the ratio of indentation depth to the film thickness (d/t) exceeds a critical value, then the measured mechanical properties are going to be influenced by the substrate material and it is no longer characteristics of the coating. [43,52,53] Therefore, one needs to identify the penetration depth by monitoring the phenomena with respect to indentation load. The critical d/t ratio %10% is preferred.…”

Evaluating the role of composition and local structure on alkali out‐diffusion in glasses for thin‐film solar cells

“…The estimated elastic modulus also showed a similar trend ( Figure 5C). In the case of the NL series, stronger bonds influenced the network rigidity leading to a linear increase in elastic modulus, 60 whereas roughly linear decrease due to weaker bonds was noted for the NK series ( Figure 5C). The Vicker's microhardness (H) for the NL as well as the NK series increased nonlinearly ( Figure 5D).…”