Mach zinder photonics crystal fiber interferometer techniques for thin film thickness measurement

• Main Authors: Mahdi, Bushra R., Aljbar, Nahla. A., Hamoody, Jamal F., Mahmood, Aseel I., J-Albazaz, Dunya A.
• Format: Conference Proceeding
• Language: English
• Subjects: Crystal fibers; Film thickness; Infrared lasers; Laser beam welding; Optical fibers; Sensors; Thickness measurement; Thin films; Titanium; Titanium dioxide
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0095410

In this paper, a crystalline optical fiber sensor was designed and implemented using Mach Zinder technology to measure the thickness of thin films from a colloidal solution gel of titanium dioxide simultaneously. Mach-Zinder technologies are implemented by welding a 2 cm long piece of photon fiber with a solid core With single-mode optical fibers (SMF - SCF - SMF) forming the sensor body, which is tested by coating a thin layer of a colloidal solution of titanium dioxide gel on the surface of the SCF. The sensor was fed to an infrared laser source at a center with a width of 1550 nm. Layers of different thicknesses were deposited on the surface of the sensor by dipping method, including the collapse zone. The thickness of the membrane was based on the time period to submerge the sensor structure, which is 30 seconds, 60 seconds, and 90 seconds. A series of experiments were conducted using a laser source, a homemade sensor and a spectrophotometer. The spectra were collected in the ranges of 1540-1556 nm for the three precipitated thin films. The results showed that the manufactured sensor has the ability to distinguish a thin film thickness ranging from 10-50 µm. The sensor is characterized by its simple components, manufacturing, low cost, accuracy and high reproducibility. This opens the door to thin film measuring applications in scientific laboratories. The manufactured sensor demonstrated our limited ability to measure the thin film with a sensitivity of 120 pm / μm.