Micro assembly

After the micro wear tests, the dependence of worn depth of PTFE and PTFE/Si3N4 film on load is shown in Fig. 13. The worn depth of both PTFE and PTFE/Si3N4 film is in the nanometer scale. It can be seen that the worn depth increases linearly with load. However, the worn depth of PTFE/Si3N4 multilayers is about one-tenth of PTFE film at the same load. All these results demonstrate that the wear resistance of PTFE/Si3N4 multilayers is greatly improved after micro-assembling of soft and hard layers. 

SC Esener, D Hartmann, MJ Heller, JM Cable. DNA-assisted micro-assembly a heterogeneous integration technology for optoelectronics. Proc. SPIE Critical Reviews of Optical Science and Technology, Heterogeneous Integration, San Jose, CA, 1998, pp 65-68. 

Huang, T. T., Geng, T., Akin, D., Chang, W. J., Sturgis, J., Bashir, R., Bhunia, A. K., Robinson, J. P., and Ladisch, M. R. (2003c). Micro-assembly of functionalized particulate monolayer on C-18-derivatized SiOi surfaces. Biotechnol. Bioeng. 83, 416 27. 

Bao, Z. H., Weatherspoon, M. R., Shian, S., etal, Chemical reduction of three-dimensional silica micro-assemblies into microporous silicon replicas. Nature 2007, 446, 172-175. 

Michaeli, W. Ziegmann, C. Micro assembly injection moulding for the generation of hybrid microstructures. Microsyst. Technol. 2003, 9, 427 30. 

Worn H, Seyffied J, Fahlbusch S, Biirkle A (2000) Flexible microrobots for micro assembly tasks. Proc Int Symp Micromech Hum Sci 27 22-25... 

Replication techniques are available for transforming complex silica shapes into the corresponding shapes of various polymers. Ihe process can also be extended in the opposite direction, by converting the silica into silicon. Specifically, a low-temperature reduction process has been developed to convert three-dimensional nanostructured silica micro-assemblies into microporous nanocrystalline silicon replicas. Such materials could be useful in a variety of applications, including sensors and biomedical devices. 

Baneqee HD, Sen S, Acharya HN, (1982) Investigations on the production of silicon from rice husks by the magnesium method. Mater Sci Eng 52 173-179 Bao Z, Weatherspoon MR, Shian S, Cai Y, Graham PD, Allan SM, Ahmad G, Dickerson MB, Church BC, Kang Z, Abernathy HW III, Summers CJ, Liu M, Sandhage KH (2007) Chemical reduction of three-dimensional silica micro-assemblies into microporous silicon replicas. Nature 446 172-175... 

Micro assembly. While most of the technology used to fabricate parts of millimeter or micrometer size could be copied and modified from microelectronic fabrication processes, this is not true for micro assembly. There are scarcely any devices suitable for a small- or medium-scale automated assembly of micromechanical systems. Micro assembly opens a broad field of potential applications for new actuator principles. An example is the handling of millimeter-sized, lightweight parts under clean-room conditions and with small operational space available. 

General Aspects. Mechanical grippers have a variety of applications and for that reason will very likely be the most often used grippers also in micro assembly. There are some differences to common assembly procedures to be considered when assembling very small parts. For grippers, the required properties are briefly summarized ... 

SM actuators may have very many different shapes and offer a variety of shape changes (i. e. actuator strokes). This property can be exploited so as to adapt the SM elements shape to the actuating task. As an application example, a miniature parallel gripper with electrically heated SM wires integrated into its mechanical structure was presented. Further on the performance of pseudo-elastic shape memory flexure hinges in parallel robots for micro-assembly tasks was shown. The future opportunity for thin-fllm SM actuators to drive micromechanical systems and devices was demonstrated by a miniature silicon gripper. 

Hesselbach, J. Raatz, A. Kunzmann, H. Performance of Pseudo-Elastic Flexure Hinges in Parallel Robots for Micro-Assembly Tasks. Annals of the CIRP, Vol. 53/1, (2004), pp. 329-332... 

Figure 15.17 Fluidic characterization of the micro-assembled PPy membrane valve. Pressure drop across the valve 50 kPa.

Worn H, Seyfried J, Fahibusch S, Biirkle A (2000) Flexible Microrobots for Micro Assembly Tasks. Proceedings of the International Symposium on Micromechatronics and Human Science, 22-25 Oct 2000... 

Structured micro-assemblies built from nanoparticle primary subunits can be classified into several categories arranged, hierarchical, and oriented nanoparticle assemblies. In addition to this, one-, two-, and three-dimensional systems exist under each of these divisions. Methods of preparation can differ vastly depending on the material being synthesized or processed, i here is hardly a universal method that can be applied for the majority of chemistries, but there are several general approaches involving wet chemical techniques that are commonly used. Examples of commonly used techniques include solvothermal, sol-gel processing, surfactant-assisted synthesis, or solvent-controlled synthesis [73]. 

Hahn-Schickard-Gesellschaft — Institute for Micro Assembly Technology (HSG-IMAT), 70174... 

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