The detection and active monitoring of hydrogen gas levels is essential in many areas of industry including manufacturing, storage, and transport of this gas. Previously, methods used to detect hydrogen gas have relied upon monolithic technologies to create resistive-based sensors which are impractical for many applications requiring electrical isolation or operation in the presence of strong electromagnetic fields. Materials can be sputter deposited along cylindrical optical fiber-based sensors to create novel fiber-optic chemical sensors. Herein, the mechanisms allowing the detection of hydrogen gas using a modified Extrinsic Fabry-Perot Interferometric (EFPI) sensor are presented in this work. A new custom-designed, custom-built radio frequency (RF) magnetron sputtering system has been used to deposit thin films of palladium metal along with cylindrical substrates. The surface morphology of the deposited films are investigated using a variety of analytical tools, including Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (AES), and Auger Electron Spectroscopy (AES). The system is used to deposit thin films of palladium along a cylindrical EFPI fiber-optic sensor to produce a new fiber-optic hydrogen gas sensor. Experimental results obtained in a controlled hydrogen atmosphere are used to demonstrate the high resolution and fast response time associated with these new hybrid sensors. / Master of Science