我们研究的微型K~+-IS FET的结构如图1所示.K~+-IS FET的响应机理,主要是由电解液-敏感膜界面的界面势的产生,导致K~+-ISFET的沟道电导的变化,引起漏源电流的改变,从而可检测溶液中的K~+离子活度.关于界面势的产生机理有许多解释,总括起来,目前用得较多的模型有两种,一种是扩散模型,另一种是格点桥键模型.我们认为,对非阻挡型敏感膜(PVC膜),用扩散模型解释其响应机理较为合适. The structure of the miniature K ~ + -IS FET we studied is shown in Figure 1. The response mechanism of the K ~ + -IS FET is mainly due to the generation of the interface potential at the electrolyte-sensitive membrane interface, Channel conductivity changes, causing changes in the drain-source current, which can detect the activity of K ~ + ions in the solution. There are many explanations on the mechanism of interfacial potential. To sum up, there are two types of models that are currently used more, One is the diffusion model and the other is the lattice-bridge model.We think that the non-barrier sensitive film (PVC film), using the diffusion model to explain the response mechanism is more appropriate.