Ions Sensitive Field Effect Transistors (ISFETs) are becoming the platform sensors for important chemical and biomedical applications. However, the accuracy of ISFET output measurement is greatly affected by the prese...Ions Sensitive Field Effect Transistors (ISFETs) are becoming the platform sensors for important chemical and biomedical applications. However, the accuracy of ISFET output measurement is greatly affected by the presences of low-frequency noise, drift and slow response of the device. This requires more safety in measured results and the tools of analysis. In this paper, we present fundamental limits on the sensitivity of ISFETs micro-sensors, arising from intrinsic and extrinsic noise sources. We developed an algorithm in MATLAB in order to model the frequency analysis of the 1/f noise in ISFET sensor using Hooge theory. We have shown that the 1/f noise of the ISFETs sensors is due to both the electrochemical system (pH solution) and the MOS component (canal size, insulator thickness). The temperature effect on the ISFET noise and the signal conditioning are also performed.展开更多
The advantages of the extended gate field effect transistor (EGFET) compared with the ion sensitive field effect transistor (ISFET) are easy package,easy preservation,insensitive light effect,and better stability.Al...The advantages of the extended gate field effect transistor (EGFET) compared with the ion sensitive field effect transistor (ISFET) are easy package,easy preservation,insensitive light effect,and better stability.Although EGFET has above advantages,there are still some non-ideal effects such as drift etc..The drift behavior exists during the measurement process and results in the variation of the output voltage with time.We can obtain the drift value by immersing EGFET into the pH solution for 12 hours and measure the rate of the output voltage versus time after S hours.This study analyzes the sensitivity, stability,and drift effect of the EGFET based on the structure of the ruthenium oxide/silicon (RuO_x/Si) wafer for measuring the potassium ion.The fabrication of the potassium ion sensor can be widely employed in medical detection.展开更多
文摘Ions Sensitive Field Effect Transistors (ISFETs) are becoming the platform sensors for important chemical and biomedical applications. However, the accuracy of ISFET output measurement is greatly affected by the presences of low-frequency noise, drift and slow response of the device. This requires more safety in measured results and the tools of analysis. In this paper, we present fundamental limits on the sensitivity of ISFETs micro-sensors, arising from intrinsic and extrinsic noise sources. We developed an algorithm in MATLAB in order to model the frequency analysis of the 1/f noise in ISFET sensor using Hooge theory. We have shown that the 1/f noise of the ISFETs sensors is due to both the electrochemical system (pH solution) and the MOS component (canal size, insulator thickness). The temperature effect on the ISFET noise and the signal conditioning are also performed.
文摘The advantages of the extended gate field effect transistor (EGFET) compared with the ion sensitive field effect transistor (ISFET) are easy package,easy preservation,insensitive light effect,and better stability.Although EGFET has above advantages,there are still some non-ideal effects such as drift etc..The drift behavior exists during the measurement process and results in the variation of the output voltage with time.We can obtain the drift value by immersing EGFET into the pH solution for 12 hours and measure the rate of the output voltage versus time after S hours.This study analyzes the sensitivity, stability,and drift effect of the EGFET based on the structure of the ruthenium oxide/silicon (RuO_x/Si) wafer for measuring the potassium ion.The fabrication of the potassium ion sensor can be widely employed in medical detection.
