Nowadays, micro–nanomanufacturing technology and micro–nanodevices have seen some development, but many micro–nanodevices and microelectromechanical systems have not been practically used as products. This is because dispensing technology used in micro–nanosize encapsulation and assembly is one of the main obstacles, such as the size of the glue point, the amount of glue, and precision. In this paper, on the basis of the principle of transfer printing, an ultra-microautomatic dispenser method of pL-fL grade pipetting needle glue transfer type is proposed. This method involves controlling the pipetting needle pass through the capillary tube filled with glue liquid by the precision micro-displacement drive platform, making the terminal of the pipetting needle attach to a trace amount of adhesive, and then leaving a part of the glue liquid on the base plane to form tiny glue points using the adhesive force of glue liquid in contact with the base plane and the pulling force of the drive platform on glue liquid. The diameter of the glue point is about dozens of microns, and the amount of glue is pL of magnitude. In this paper, the dispensing process was simulated under different parameters, and the main factors affecting the dispensing process were preliminarily determined. The influence law of the diameter of the pipetting needle, movement speed, and residence time on the diameter of the glue point was analyzed by orthogonal experiment. On the basis of the influencing factors and laws obtained above, the automatic distribution of fL grade glue liquid was realized through a reasonable configuration of parameters. The minimum diameter of the glue point was 13.2 µm, and the volume was 26.3 fL.

Due to the rapid development of precision micro-manufacturing technology, the connection and assembly process of precision micro devices put forward higher requirements for the volume and accuracy of micro dispensing technology. In this paper, an ultra-micro dispensing method based on the surface tension is proposed. It can realize micro size feature adhesive dispensing, here, adhesive droplet volume is in range of fL—pL. The transferring needle passes through the thin tube filled with adhesive liquid, and correspondingly, a micro amount of adhesive liquid is attached to the needle depending on the adhesion between needle and liquid. Then, the adhesive force between adhesive liquid and dispensing surface and the liquid’s self surface tension make a micro amount of adhesive liquid left on the dispensing surface and form a droplet. In this paper, we carried out a set of detailed single factor experimental study, and systematically analyzed the affection of main working parameters, including the diameter of transferring needle, dispensing speed, dispensing distance between the tip of needle and dispensing surface and the viscosity of adhesive, on dispensing results. Based on the above research results about working parameters characteristics, an ultra-micro dispensing process at fL level volume was realized. Diameter of adhesive droplet could be as small as 22.4 μm, and volume reached to 228 fL. Ultra-micro automatic continuous dispensing is realized through automatic moving path planning of transferring needle by CAD program, and we obtained two droplet dot arrays with different layouts. The proposed ultra micro dispensing system can control droplet size and dispensing position precisely. The deviation of adhesive droplet diameter is less than 2.2 μm, and the position deviation is within 1.58 μm.

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