Temperature Dependent Electrical Characteristics of SiO2 and HfO2 based BIOFETs for Enhanced Biosensing Applications

This study presents a systematic investigation of temperature-dependent electrical characteristics in Silicon Dioxide (SiO2) and Hafnium Dioxide (HfO2) based bio-sensitive field-effect transistors (BIOFETs) across a temperature range of $25^{\circ} \mathrm{C}$ to $200^{\circ} \mathrm{C}$. Through comprehensive simulation and analysis, we examine the thermal effects on critical electrical parameters including drain current, transconductance, threshold voltage, and mobility variations. Our findings demonstrate that $\mathbf{H f O}_{2}$-based BIOFETs exhibit superior electrical characteristics at moderate temperatures $\left(75^{\circ} \mathrm{C}-\right. 125^{\circ} \mathrm{C}$), maintaining enhanced performance stability compared to SiO2 counterparts. The investigation reveals that HfO2 devices demonstrate up to $35 \%$ higher drain current and $28 \%$ improved transconductance at optimal operating temperatures, attributed to their superior dielectric properties and reduced interface trap density. Statistical analysis confirms distinct temperature coefficients for both materials, with HfO2 showing optimal performance at $100^{\circ} \mathrm{C}$ where electrical characteristics peak before gradual degradation at higher temperatures. The threshold voltage shift analysis indicates better thermal stability in $\mathbf{H f O}_{\mathbf{2}}$-based devices with minimal voltage drift $(\pm 50 \mathrm{mV})$ compared to SiO2 devices $(\pm 120 \mathrm{mV})$ across the studied temperature range. These findings establish HfO2 as the preferred dielectric material for temperature-sensitive biosensing applications requiring consistent electrical performance under varying thermal conditions.