FUNCTIONAL TUNGSTEN-BASED THIN FILMS AND THEIR CHARACTERIZATION

Anodization is a technique that can be used to create thin layers of oxide on the surface. Thin oxide layers have been found to be useful in a variety of applications, including emitters of electrons. Tungsten is still often choice for cold field emitters in commercial microscopy applications. His suitable quality can be improved even more by deposition of thin layer. Not only emission characteristic can be improved, but also emitter operating time can be prolonged. Tungsten oxide is known for its excellent resistance to corrosion and chemical attack, which is due to its stable crystal structure and the strong chemical bonds between tungsten and oxygen atoms. Many techniques were applied for this purpose, with various advantages and disadvantages. For this work anodization was chosen because of controllable uniform material coverage and easy accessibility without the need for expensive complex equipment. The anodization process involves applying an electrical potential to tungsten while it is immersed in an electrolyte solution. This causes a thin layer of tungsten oxide to form on the surface of the metal. The thickness and properties of the resulting oxide layer can be controlled by adjusting the anodization conditions, such as the electrolyte solution, voltage, and the duration of the process. In this work, H3PO4 was used as electrolyte To test whether these tungsten oxide layers would be viable for electron emitters, for use in electron guns and other devices that require high-quality electron emitters, we put them through a series of tests. Properties were evaluated using appropriate techniques. In general, anodization of tungsten to create thin tungsten oxide layers is a promising technique for producing high-quality electron emitters.