|Byeong Wan An, Sanghyun Heo, Sangyoon Ji, Franklin Bien, and Jang-Ung Park|
|Nature Communications (2018)|
We developed a transparent and ﬂexible, capacitive ﬁngerprint sensor array with multiplexed, simultaneous detection of tactile pressure and ﬁnger skin temperature for mobile smart devices. In our approach, networks of hybrid nanostructures using ultra-long metal nanoﬁbers and ﬁner nanowires were formed as transparent, ﬂexible electrodes of a multifunctional sensor array. These sensors exhibited excellent optoelectronic properties and outstanding reliability against mechanical bending. This ﬁngerprint sensor array has a high resolution with good transparency. This sensor offers a capacitance variation ~17 times better than the variation for the same sensor pattern using conventional ITO electrodes. This sensor with the hybrid electrode also operates at high frequencies with negligible degradation in its performance against various noise signals from mobile devices. Furthermore, this ﬁngerprint sensor array can be integrated with all transparent forms of tactile pressure sensors and skin temperature sensors, to enable the detection of a ﬁnger pressing on the display.
Transparent and Flexible Fingerprint Sensor Array with Multiplexed Detection of Tactile Pressure and Skin Temperature.