Integrating micro chips for electronic skin

To closely replicate natural skin, it is however necessary to interconnect a big number of individual sensors. This challenging task became a major obstacle in realizing electronic skin. First demonstrations were based on an array of individual sensors addressed separately, which unavoidably resulted into a tremendous number of electronic connections. In order to reduce the necessary wiring, an important technology step had to be done. Namely, complex electronic circuits, such as shift registers, amplifiers, current sources and switches must be combined with individual magnetic sensors to achieve fully integrated devices.

Researchers from Dresden, Chemnitz and Osaka could overcome this obstacle in a pioneering active matrix magnetic sensor system presented in a recent article of the journal Science Advances. The sensor system consists of a 2 x 4 array of magnetic sensors, an organic bootstrap shift register, required for controlling the sensor matrix, and organic signal amplifiers. The special feature is that all electronic components are based on organic thin-film transistors and are integrated within a single platform. The researchers demonstrate that the system has a high magnetic sensitivity and can acquire the two-dimensional magnetic field distribution in real time. It is also very robust against mechanical deformation, such as bending, creasing or kinking. In addition to full system integration, the use of organic bootstrap shift registers is a very important development step towards active matrix electronic skin for robotic and wearable applications.

Prof. Dr. Oliver G. Schmidt, Director at the Leibniz Institute for Solid State and Materials Research Dresden and Dr. Daniil Karnaushenko on the next steps: "Our first integrated magnetic functionalities prove that thin-film flexible magnetic sensors can be integrated within complex organic circuits. Ultra-compliant and flexible nature of these devices is indispensable feature for modern and future applications such as soft-robotics, implants and prosthetics. The next step is to increase the number of sensors per surface area as well as to expand the electronic skin to fit larger surfaces."