In this work, we describe a method of controlling the size of a conducting polymer (CP) junction between one ultramicroelectrode (UME) and a substrate electrode using a scanning electrochemical microscopy (SECM) configuration with a variable resistor connected to the UME tip. The CP is grown by electro-polymerization from the UME tip to the substrate until contact occurs. Because of the resistor, the effective potential applied to the UME tip decreases dramatically as soon as contact is established between the electrodes. Consequently, polymer growth self-terminates, since the potential is too low to continue monomer oxidation and electropolymerization. In this way, by changing the external resistance it is possible to control the size of the CP junction, as polymer growth stops once the desired junction is established. Nanowire junctions whose conductance is controlled by a few hundred polymer strands can thus be generated in a reproducible way.

在这项工作中，我们描述了一种使用扫描电化学显微镜（SECM）配置以及连接到UME尖端的可变电阻器来控制一个超微电极（UME）和衬底电极之间的导电聚合物（CP）结尺寸的方法。通过电聚合从UME尖端到基板生长CP，直到发生接触为止。由于电阻器的存在，一旦在电极之间建立了接触，施加到UME尖端的有效电势就会急剧下降。因此，由于电位太低而无法继续进行单体氧化和电聚合，因此聚合物生长会自行终止。这样，通过改变外部电阻，可以控制CP结的尺寸，因为一旦建立了所需的结，聚合物就会停止生长。