In the technique developed by ETH doctoral student Luca Hirt of the Laboratory of Biosensors and Bioelectronics, the print head can print sideways, meaning that overhangs can be printed without templates.
At the heart of this system is a moveable micropipette mounted on a leaf spring, which can be positioned extremely precisely. Hirt has been investigating the possibility of using FluidFM for printing processes. In particular, he is interested in using this technique to electro-deposit dissolved metals and other substances on to a conductive substrate.
Using a computer to control the movement of the micropipette, the researchers can print three-dimensional objects pixel by pixel and layer by layer. At present, the scientists can produce individual 3D pixels with diameters ranging from 800nm to more than 5µm, and can combine these to form larger 3D objects.
The researchers said that FluidFM can be used to create objects out of other metals as well as copper, and may even be suitable for 3D printing with polymers and composite materials.
An advantage of this method over other 3D microprinting processes is that the forces acting on the tip of the pipette can be measured via the deflection of the leaf spring on which the micropipette is mounted. "We can use this signal as feedback. Unlike other 3D printing systems, ours can detect which areas of the object have already been printed," said Hirt, making it easier to automate the printing process.