Optimization of optical properties of Ba0.2Sr0.8TiO3 thin films for a glucose sensor implementation

The development of non-invasive blood glucose measuring devices continues to be developed. The photosensor is one of the instruments for detection the blood glucose, and the high performance of sensor is depending on the optical properties. Consequently, the observation about optical properties of Ba0.2Sr0.8TiO3 (Barium Strontium Titanate) is important. In this paper, a solution of Ba0.2Sr0.8TiO3 (Barium Strontium Titanate) with chlorophyll extract from spinach and papaya leaves has been deposited on the p-type Si (100) by spin coating technique. This research aims to find the effects of presence of chlorophyll in the Ba0.2Sr0.8TiO3 films according to their optical properties and phonon mode. The film fabricated consisting of BST, BST with 2.5% spinach chlorophyll, BST with 5% spinach chlorophyll, BST with 2.5% papaya chlorophyll, and BST with 5% papaya chlorophyll. Therefore, the characterization was using UV-Vis spectrophotometer and micro Raman spectroscopy. The result showed that the addition of papaya chlorophyll have the optimal character than spinach chlorophyll. BST with papaya chlorophyll showed a significant decrease in the energy gap. Also, it has a phonon mode with a Raman shift that supports the result.