Study of Functional Nanostructured Electrode Devices for Biomedical Detection

• Main Authors: LAN, YUAN-CHUN, 藍元駿
• Other Authors: CHANG, TIEN-LI
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/57701461719379660725

碩士 === 國立臺灣師範大學 === 機電工程學系 === 102 === Since the innovation of the nanotechnology, many studies of design and fabricate the sensors are via nano-process technology in recent years. The biomedical detection is especially considered as an important event. Compared with the hospital-mainframe platform detection, the advantages of biomedical on-chip sensing devices are the high functionality, light weight, lower cost and real time. Because it is the portable devices with more less samples for detection, people can use them at home and then obtain the information about their bodies early. Hence, the patients can get effectively treatment early in the disease. The biomedical market of on-chip sensing devices is also significant and concerned. Generally, the on-chip sensors are mostly one-dimensional nanowire-based structures on biomedical detection currently. The nanowire process is instability where the nanowires uniform on electrodes is very difficult. So the nanowire-based sensing chip cannot be easily to mass production. In this study, titanium nitride (TiN) nanowire sensors arrays are fabricated by electron-beam lithography and plasma etching. Herein the width of nanowire is 50 nm. On the other hand, this study uses the nanowire structures to develop and fabricate the horizontal structure sensors in which the concept is resistive random-access memory (RRAM) with a tungsten oxide layer. The behavior of electrical detection can be measured and discussed for two types of structure sensors. For the gas detection, the oxygen can be detected by TiN nanowire sensors with high sensitivity and reproducibility. When the oxygen concentration is 0.8 ppm, the response of the resistance indicates 45%. In addition, RRAM-based sensors have higher change of resistance and higher response when leaving atmospheric condition in the chamber. The response is up to 145% at low resistance state especially. It shows that RRAM-based sensor with a tungsten oxide layer has a high sensing capability for the detection of remaining gases at the atmosphere. For the biomolecule detection, the glucose can be used in this study. At the glucose concentration of 1052 ng/μl, the high resistance state of RRAM-based sensor has the response of the resistance which is 18535%. This value is much higher than nanowire-based sensor where response of the resistance is with 2146%. When concentration of glucose is higher than 1052 ng/μl, the resistance at the low resistance state changes obviously. It can be seen that it will have better effect at the low resistance state when the blood glucose concentration is over the normal range. Consequently, RRAM-based sensors are able to possible to be developed for detection of blood glucose.