本文使用化学气相沉积（Chemical Vapor Deposition，CVD）石墨烯制作了高灵敏度、低噪声的液栅型石墨烯场效应管（Solution-Gated Graphene Field Effect Transistors，SGFETs），并测试了该器件对磷酸盐缓冲液（Phosphate Buffered Saline，PBS）浓度和pH的响应特性. 随缓冲液浓度的增大，SGFETs转移特性曲线的最小电导点向左偏移，偏移量与溶液浓度的自然对数呈线性关系. 随pH的增大，其最小电导点向右偏移，偏移量与溶液pH呈线性关系. 该响应特性对石墨烯生化传感器排除外界影响因素有一定的指导作用.
High-sensitivity and low-noise solution-gated graphene field effect transistors (SGFETs) were fabricated using chemical vapor deposition (CVD) graphene as a channel material, and their response characteristics to concentration and pH of phosphate buffered saline (PBS) were measured. The minimum conductance point shifted to left with increasing concentration, and the offset showed a linear relationship with the natural logarithm of concentration. While, the minimum conductance point shifted to right with increasing pH, and the offset showed a linear relationship with pH. The research on these response characteristics may give proper guidance to SGFETs’s application.
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