A novel dry-type glucose sensor based on a metal-oxide-semicoductor capacitor (MOSC) structure with HRP+GOD catalyzing layer

The paper propose a novel dry-type glucose sensor based on the MOSC structure using a SiO₂ gate dielectric in conjunction with an HRP (horseradish peroxidase) + GOD (glucose oxidase) catalyzing layer. The tested glucose solution was dropped directly onto the window opened on the SiO₂, with a coating of HRP+GOD catalyzing layer on top of the gate dielectric. From the C-V characteristics of the MOSC found that the glucose solution can induce an inversion layer on the silicon surface causing a gate leakage current flowing along the SiO ₂ surface. The gate current changes DeltaI before and after the drop of glucose solution exhibits a near-linear relationship with increasing glucose concentration. The highest linearity occurs when the gate is forward biased at +4V and +5V. The DeltaI sensitivity is about 1.76 nA/cm²/M, and the current is quite stable 20 to 30 min after the drop of the glucose solution