Search

To realize quantum tunneling applications with movable electrodes, sharp tips with radii down to several tens of nanometers are necessary. The use of a focused ion beam (FIB) and focused electron beam (FEB) with a gas injection system (GIS) allows the integration of geometries in the nanoscale directly into micro and nano systems. However, the implementation of the tunneling effect clearly depends on the material. In this work, a metal-organic precursor is used. The investigation of the prepared tunneling electrodes enables an insight into FIB/FEB parameters for the realization of quantum tunneling applications. For this purpose, a high-resolution transmission electron microscopy (HRTEM) analysis is performed. The results show a dependence of the material nanostructure regarding platinum (Pt) grain size and distribution in an amorphous carbon matrix from the used beam and the FIB currents. The integration of the tips into a polysilicon (PolySi) beam and measuring the current signal by approaching the tips show significant differences in the results. Moreover, the approach of FEB tips shows a non-contact behavior even when the tips are squeezed together. The contact behavior depends on the grain size, proportion of platinum, and the amount of amorphous carbon in the microstructure, especially at the edge area of the tips. This study shows significant differences in the nanostructure between FIB and FEB tips, particularly for the FIB tips: The higher the ion current, the greater the platinum content, the finer the grain size, and the higher the probability of a tunneling current by approaching the tips.

The development and manufacturing of high-precision micro-mechatronic systems (MMS) is a challenging task, and the high demand for individualized products complicates the engineering design process (EDP) in particular. The established EDP for MMS is not designed for individualized products. This article gives an overview of the challenges (critical factors) in product development and manufacturing of individualized MMS (iMMS), a novel definition of iMMS, and describes a new qualitative methodology in order to tailor an EDP based on use cases, so-called “Tailored EDP-Methodology” (TEDP-Methodology). This TEDP-Methodology allows creating use-case-based product groups through the abstraction of the use cases and evaluating the requirements, which is essential to tailor or develop a new EDP. For the development of this new approach, a literature review and qualitative content analysis are prefaced. The TEDP-Methodology is critically examined and validated with a real case study for the development and manufacturing of an iMMS. This study shows critical points within the EDP. It shows fields of action for innovative tools to support the development process of iMMS and requirements for different product groups within iMMS. This article has both theoretical and practical implications.

Thermoset materials offer a multitude of advantageous properties in terms of shrinkage and warpage as well as mechanical, thermal and chemical stability compared to thermoplastic materials. Thanks to these properties, thermosets are commonly used to encapsulate electronic components on a 2nd-level packaging prior to assembly by reflow soldering on printed circuits boards or other substrates. Based on the characteristics of thermosets to develop a distinct skin effect due to segregation during the molding process, the surface properties of injection molded thermoset components resemble optical characteristics. Within this study, molding parameters for thermoset components are analyzed in order to optimize the surface quality of injection molded thermoset components. Perspectively, in combination with a reflective coating by e.g., physical vapor deposition, such elements with micro-integrated reflective optical features can be used as optoelectronic components, which can be processed at medium-ranged temperatures up to 230 °C. The obtained results indicate the general feasibility since Ra values of 60 nm and below can be achieved. The main influencing parameters on surface quality were identified as the composition of filler materials and tool temperature.

Reconfigurable manufacturing systems (RMS) can be used to produce micro-assembled products that are too complex for assembly on flat substrates like printed circuit boards. The greatest advantage of RMS is their capability to reuse machine parts for different products, which enhances the economical efficiency of quickly changing or highly individualized products. However, often, process engineers struggle to achieve the full potential of RMS due to product designs not being suited for their given system. Guaranteeing a better fit cannot be done by static guidelines because the higher degree of freedom would make them too complex. Therefore, a new method for generating dynamic guidelines is proposed. The method consists of a model, with which designers can create a simplified assembly sequence of their product idea, and another model, with which process engineers can describe the RMS and the procedures and operations that it can offer. By combining both, a list of possible machine configurations for an RMS can be generated as an automated response for a modeled assembly sequence. With the planning tool for micro-assembly, an implementation of this method as a modern web application is shown, which uses a real existent RMS for micro-assembly.

Micro manufacturing is dealing with the fabrication of structures in the order of 0 [...]

Faster product lifecycles make long-term investments in machines for micro assembly riskier. Therefore, reconfigurable manufacturing systems gain more and more attention. But most companies are uncertain if a reconfigurable manufacturing system can fulfill their needs and justify the initial investment. New and improved techniques for product development have the potential to foster the utilization and decrease the investment risk for such systems. In this paper, four different methods for product development are reviewed. A set of criteria regarding micro assembly on reconfigurable manufacturing systems RMS is established. Based on those criteria and the assessment, a novel approach for a product development method is provided, which tries to combine the strengths of the beforehand presented approaches. It focuses on the conceptual design phase to overcome the customers’ uncertainty in the development process. For this, an abstract representation of a micro-assembly product idea as well as a decision tree for joining processes are established and validated by real product ideas using expert interviews. The validation shows that the conceptual design phase can be used as a useful tool in the product development process in the field of micro assembly.

A novel optical incremental and absolute encoder based on an optical application-specific integrated circuit (opto-ASIC) and an encoder disc carrying micro manufactured structures is presented. The physical basis of the encoder is the diffraction of light using a reflective phase grating. The opto-ASIC contains a ring of photodiodes that represents the encryption of the encoder. It also includes the analog signal conditioning, the signal acquisition, and the control of a light source, as well as the digital position processing. The development and fabrication of the opto-ASIC is also described in this work. A laser diode was assembled in the center on top of the opto-ASIC, together with a micro manufactured polymer lens. The latter was fabricated using ultra-precision machining. The encoder disc was fabricated using micro injection molding and contains micro structures forming a blazed grating. This way, a 10-bit optical encoder with a form factor of only 1 cm3 was realized and tested successfully.