Monolithic Inkjet Printed, Skin-Attachable Optoelectronic Sensors for Continuous Blood Pressure Monitoring

• Applicant: Dr. Sanghoon Baek
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering ; Biomedical Systems Technology
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 509814213

The goal of this research project is to develop digitally printed optoelectronic sensors that can continuously and non-invasively monitor blood pressure when attached to the skin, using flexible and biocompatible films. I will achieve this by successfully realizing the following objectives: (1) Development of inkjet-printed optoelectronic devices on biocompatible substrates. Organic optoelectronic devices such as OLEDs, OLECs, OPDs, and OFETs will be developed by inkjet printing on biocompatible substrates. Skin-like ultrathin biocompatible substrates will be investigated and optimized. Functional optoelectronic materials will be engineered to become printable. The optoelectronic elements will be fabricated and characterized and the effect of printing parameters on device performance will be investigated. (2) Development of an optimized reflectance-mode photoplethysmography (PPG) sensing unit. The monolithic integration process of multiple optoelectronic components on a single substrate will be investigated. OPDs will be vertically integrated onto OFETs to maximize the light detection sensitivity. An inkjet-printed reflectance-mode PPG sensing unit will be demonstrated. Geometrical parameters such as device size, shape, and layout will be optimized to result in the optimum signal acquisition, which is a process that enables personalization. (3) Development of blood pressure (BP) monitoring system. Spatiotemporal mapping of PPG signals utilizing a matrix of sensing units will be demonstrated to obtain an optimal reading. BP will be estimated by acquiring PPG signals at different sensing positions and calculating the velocity. The sensing positions on the body will be precisely investigated to improve accuracy. Finally, a printed skin-attachable system that can monitor BP non-invasively and continuously will be demonstrated.

• DFG Programme: WBP Position