Fluidic Assembly of Microscopic Objects – Exploring Hybrid Deterministic Transport and Statistic Surface Tension Based Assembly and Interconnection Concepts – Fundamentals, Assembly Kinetics, and Scaling Limits

• Applicant: Professor Dr. Heiko Jacobs, since 5/2021
• Subject Area: Microsystems ; Production Automation and Assembly Technology
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 438083845

Background and Motivation: While robotic machines dominate the manufacturing world there are applications where the established processes of serial pick and place reach limits. For example, these established processes are challenged if the assembly deals with microscopic objects (1-100 micrometer) or the assembly of large numbers of parts at high throughput. At the other extreme, nature produces materials, structures, and living systems by self-assembly on a molecular length. Self-assembly-based fabrication strategies have been established to assemble repetitions of the same unit type with surprisingly high yields, throughput, and precision. While successful, the assembly of heterogeneous systems that contain distinctly different parts continues to be a hard problem (3 different parts is difficult, 5 different parts has not been demonstrated). “Self-assembly only” solutions are likely going to fail with increased levels of heterogeneity. We believe that some kind of controlled component transport and sequence is necessary to assembly sites much like what is done in conventional manufacturing. Objectives: In recognition of this current challenge we propose to research if a cross-disciplinary fusion of deterministic and statistical assembly methodologies is capable to increase the level of heterogeneity. Specifically, the proposed approach merges deterministic “Component Transport (WP1)” with the concept of statistic “Fluidic Surface Tension Directed Self-Assembly (WP2)”. The task for the component transporter is to take disparate microscopic objects (A, B, C) from separate sources (A, B, C) and to transport these microscopic objects to predetermined self-assembly sites. The first self-assembly site is referred to as “Surface Self-Assembly Sites”. Here, the technological goal is to enable heterogeneous flip-chip self-assembly of different (A, B, C) microscopic chips with multiple interconnects at predetermined surface locations (A, B, C). The second self-assembly site is referred to as “Aggregation Self-Assembly Sites”. Aggregation self-assembly sites are locations where different objects are assembled into a larger aggregated (A+B+C) structure. Two testbed applications are proposed to apply the gained knowledge. The surface self-assembly process will be applied to distribute microscopic LEDs and transistors over large area substrates. The aggregation assembly site approach is applied to demonstrate an “analogy to microfluidic reactor”. The reactants are replaced with microscopic parts which react in predetermined locations to assemble a larger structures.From a more fundamental science point of view, we would like to study the self-assembly events on a single component basis to understand and witness the design specific kinetics of the capturing events. The goal is to establish a correlation between the assembly kinetics of microscopic objects as a function of the energy landscape including 3D shaped topological guides and shape exclusions

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr.-Ing. Thomas Stauden, until 5/2021