Dual-gate (DG) Ion-sensitive thin-film transistor (ISTFT) pH sensors based on tin oxide (SnOx) channel and Al2O3 sensor membrane have been developed. DG SnOx thin film transistors with Al2O3 dielectrics were fabricated, illustrating effective linear current modulation under top gate bias. The SnOX DG-ISTFTs with 10-nm Al2O3 sensor membrane can operate at a low single supply voltage of −1.0 V with a low power consumption around 3 μW\mu \text{W} . In contrast to most reported ISTFT pH sensors, which show linear dependence of pH value on threshold voltage, and are not directly readable, the SnOx DG-ISTFTs exhibit linear pH dependence on directly readable drain current. We demonstrate a high sensitivity of 83.87 nA/pH and a low current hysteresis of 1.65 nA after a pH loop of 7-10-7-4-7. This enables significantly simplified readout circuits with reduced power consumption. The SnOx based DG-ISTFTs may have huge practical potential as portable and wearable biosensors and chemical sensors.

中文翻译：

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基于 SnOX 的 W 功率双栅极离子敏感薄膜晶体管，pH 值与漏极电流呈线性关系


基于氧化锡 (SnOx) 通道和 Al2O3 传感器膜的双栅极 (DG) 离子敏感薄膜晶体管 (ISTFT) pH 传感器已经开发出来。制造了具有 Al2O3 电介质的 DG SnOx 薄膜晶体管，说明了顶栅偏压下的有效线性电流调制。具有 10 nm Al2O3 传感器膜的 SnOX DG-ISTFT 可以在 -1.0 V 的低单电源电压下工作，功耗约为 3 μW\mu \text{W} 。大多数报道的 ISTFT pH 传感器显示 pH 值对阈值电压的线性依赖性，并且不可直接读取，与此相反，SnOx DG-ISTFT 表现出对可直接读取的漏极电流的线性 pH 依赖性。我们展示了 7-10-7-4-7 pH 环后的 83.87 nA/pH 的高灵敏度和 1.65 nA 的低电流滞后。这可以显着简化读出电路并降低功耗。基于 SnOx 的 DG-ISTFT 作为便携式和可穿戴生物传感器和化学传感器可能具有巨大的实际潜力。