What are the effects of oxygen point defects in AlN?
Best insight from top research papers
Oxygen point defects in AlN have several effects. First, the presence of oxygen impurities can significantly impact the anisotropy, thermal conductivity, and optical properties of AlN . Additionally, the internal quantum efficiency (IQE) of AlGaN multiple quantum wells (MQWs) is influenced by the density of point defects, including oxygen impurities . High-temperature annealing of AlN films can lead to an increase in oxygen impurity concentration, resulting in the evolution of point defects and enhanced near-ultraviolet defect peaks . Furthermore, oxygen defects in metallic TiN and semiconducting rock salt-(Al,Sc)N prefer to be in the form of substitutional and interstitial oxygen complexes, which can affect the thermionic properties of epitaxial metal/semiconductor superlattices . Overall, oxygen point defects in AlN can have significant implications for the mechanical, thermal, optical, and electrical properties of the material.
Answers from top 5 papers
More filters
| Papers (5) | Insight |
|---|---|
19 Citations | The effects of oxygen point defects in AlN include the increase in near-ultraviolet emission and the limitation of its application in deep ultraviolet optoelectronic devices. |
7 Citations | The effects of oxygen point defects in AlN are not mentioned in the provided paper. |
| Answer: The effects of oxygen point defects in AlN are not mentioned in the provided paper. | |
| The effects of oxygen point defects in AlN are not mentioned in the provided paper. | |
1 Citations | The paper mentions that oxygen impurities in AlN have a relatively large effect on the thermal conductivity and optical properties of AlN. |
Related Questions
What is the roles of oxygen vacancies on crystal structure stability and electronic property of YBCO materials.?5 answersOxygen vacancies play crucial roles in manipulating the crystal structure stability and electronic properties of YBa2Cu3O7−δ (YBCO) materials. In YBCO, oxygen vacancies impact the optical absorption peaks, causing shifts towards the infrared spectrum as vacancy concentration increases. Additionally, in oxygen-deficient perovskite oxides, such as (Pr,Ba)CoO3-δ, oxygen vacancies induce lattice modulations and influence interplanar spacings, affecting electronic and spin structures. Furthermore, in hafnium oxide, oxygen vacancies lead to structural phase transitions from monoclinic to rhombohedral phases, altering band structures and creating conducting defect bands. Oxygen vacancies in Y-doped HfO2 films control phase composition and decrease crystallization temperatures, impacting ferroelectric phase stabilization. Lastly, in SrTiO3 layers, oxygen vacancies promote Zn(II) ion diffusion, inhibiting Zn dendrite growth in aqueous zinc-ion batteries.
How do oxygen vacancies alter the bandgap of a material?4 answersOxygen vacancies in materials can alter the bandgap by narrowing it. The presence of oxygen vacancies creates mid-bandgap states, which effectively reduces the bandgap width. Highly concentrated oxygen vacancies can significantly narrow the bandgap of semiconductors, reducing the energy required for electron transition. In addition, oxygen vacancies increase the active sites on the material surface, enhancing chemisorption and improving the adsorption performance. The introduction of oxygen vacancies also improves the electrical conductivity and light absorption ability of the material. The effect of oxygen vacancies on the bandgap depends on the specific material and its composition. For example, in nonstoichiometric aluminum oxide, the presence of oxygen vacancies leads to the appearance of additional electronic states, resulting in a decrease in the energy gap. Overall, oxygen vacancies play a crucial role in altering the bandgap of materials, influencing their electronic and optical properties.
What are the causes of welding defects in aluminium?4 answersWelding defects in aluminum can be caused by various factors. One of the main causes is the presence of hydrogen in the weld metal, which leads to porosity. The solubility of hydrogen is affected by temperature and humidity, with lower temperatures and higher humidity levels resulting in higher hydrogen reserves. Another factor that contributes to welding defects is the formation of oxides on the surface of the aluminum alloy, which can lead to internal weld defects such as cracks, shrinkage cavity, or porosity. High thermal conductivity and high shrinkage in solidification also pose challenges in aluminum welding. Additionally, low temperature, high welding force, and high vibration during the welding process can adversely affect the mechanical properties of the joints. Overall, these factors need to be carefully controlled and managed to minimize welding defects in aluminum.
What is the role of the oxygen vacancies in the double perovskite LaBiCaMn2O7?5 answersOxygen vacancies play a significant role in the electric field assisted abnormal grain growth of polycrystalline perovskite phases. They can affect the resistive switching properties of metal oxide materials. In the case of LaBiCaMn2O7, the specific role of oxygen vacancies is not mentioned in the provided abstracts. However, it is known that oxygen vacancies can easily form, migrate, and strongly affect the ferroelectric behavior and piezoelectric performance of perovskite oxide ferroelectrics. Further research is needed to determine the role of oxygen vacancies in LaBiCaMn2O7 specifically.
What is point defect model in oxygen evolution reaction?5 answersPoint defect models in the oxygen evolution reaction (OER) refer to the study of defects in the crystal lattice of materials involved in the OER process. These defects, such as oxygen vacancies or substitutions, can significantly impact the catalytic activity and performance of OER electrocatalysts. The controllable synthesis of defective oxides electrocatalysts is challenging but crucial for enhancing OER performance. Oxygen defect engineering has been identified as an effective approach to regulate the OER activity of transition metal oxides. Point defect models have been used to analyze the impact of oxygen vacancies on the localized character of carriers and the charge-transfer mechanism in materials. Defects in electrocatalysts strongly influence their chemical properties and can enhance their OER performance. The study of point defect models provides insights into the behavior of defects and their influence on the oxygen activity in binary oxides.
What are the effects of defects on ferroelectric properties?5 answersDefects in ferroelectric materials have significant effects on their properties. The presence of defects, such as oxygen vacancies and ZrOx defects, influences the polarization properties of hafnium zirconium oxide ferroelectric capacitors (FeCaps). These defects can enhance the orthorhombic phase and induce lattice strain, resulting in high intrinsic polarization. In (K,Na)NbO3 (KNN) ferroelectric thin films, various multidimensional crystalline defects, including point, line, planar, and secondary phase defects, have been observed to affect the electric polarization due to strong elastic and electrostatic couplings. Dislocation loops introduced into barium titanate nanoplates via electron beam irradiation can suppress the motion of ferroelectric domain walls due to local strain fields induced by the defects. The arrangement of oxygen vacancy defects in textured bismuth titanate ceramics leads to anisotropy in the ferroelectric properties. Defect dipole complexes in ferroelectrics, such as BaTiO3 crystals, can result in large reconfigurable strains, but these strains degrade with electrical cycling due to electric field induced oxygen migration.