| Autor: |
Jeon GJ; Korea Advanced Institute of Science and Technology, Department of Materials Science and Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea., Lee SH; Hanyang University, Department of Electronic Engineering, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea., Lee SH; Korea Advanced Institute of Science and Technology, Department of Materials Science and Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea., Shim JB; Hanyang University, Department of Electronic Engineering, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea., Ra JH; Hanyang University, Department of Electronic Engineering, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea., Park KW; Korea Advanced Institute of Science and Technology, Department of Materials Science and Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea., Yeom HI; Korea Advanced Institute of Science and Technology, Department of Materials Science and Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea., Nam Y; Korea Advanced Institute of Science and Technology, Department of Materials Science and Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea., Kwon OK; Hanyang University, Department of Electronic Engineering, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea. okwon@hanyang.ac.kr., Park SK; Korea Advanced Institute of Science and Technology, Department of Materials Science and Engineering, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea. shkp@kaist.ac.kr. |
| Abstrakt: |
The fingerprint recognition has been widely used for biometrics in mobile devices. Existing fingerprint sensors have already been commercialized in the field of mobile devices using primarily Si-based technologies. Recently, mutual-capacitive fingerprint sensors have been developed to lower production costs and expand the range of application using thin-film technologies. However, since the mutual-capacitive method detects the change of mutual capacitance, it has high ratio of parasitic capacitance to ridge-to-valley capacitance, resulting in low sensitivity, compared to the self-capacitive method. In order to demonstrate the self-capacitive fingerprint sensor, a switching device such as a transistor should be integrated in each pixel, which reduces a complexity of electrode configuration and sensing circuits. The oxide thin-film transistor (TFT) can be a good candidate as a switching device for the self-capacitive fingerprint sensor. In this work, we report a systematic approach for self-capacitive fingerprint sensor integrating Al-InSnZnO TFTs with field-effect mobility higher than 30 cm 2 /Vs, which enable isolation between pixels, by employing industry-friendly process methods. The fingerprint sensors are designed to reduce parasitic resistance and capacitance in terms of the entire system. The excellent uniformity and low leakage current (<10 -12 ) of the oxide TFTs allow successful capture of a fingerprint image. |
