The effects of organic additives in a Ni sulfamate bath were investigated in order to form microprobes with a high aspect ratio. Results without the usage of additives confirmed that Ni deposits have a low aspect ratio because of in-plain spread. With the addition of propargyl alcohol, however, the form of Ni deposit changes from a flat to an oval shape. The surface morphology improved with the addition of sodium salt of saccharin, but the probe shape was flattened. Finally, the addition of PEG-4000 to a bath containing propargyl alcohol and saccharin produced probes with a fine, smooth surface and a high aspect ratio. Thus, results confirmed that satisfactory probes could be obtained with Ni electrodeposition.
