Aalto University

Research Activities

Hybrid microassembly joining robotics and capillary self-alignment


Hybrid microassembly overcome the tradeoff between speed and accuracy by joining the traditional robotic tools with the physics of self-alignment – where tiny chips will align due to surface tension of liquid or other physical forces acting at the microscale. We extensively investigate this technology and apply it to several applications in microsystem integration.


Capillary self-alignment on oleophilic /phobic patterns in air


It is difficult to make patterns that can confine adhesive in air. Using a topographical microstructure of porous ormocer functionalized with a fluorinated trichlorosilane for the oleophobic area and gold patterns for the oleophilic area, we created oleophilic/oleophobic patterns that show significant wettability contrast for adhesive (Delo 18507), with a contact angle of 119 on oleophobic part and 53 on the oleophilic part. Hybrid microassembly of SU-8 microchips on the oleophilic/oleophobic patterns has been demonstrated.


Capillary self-assembly on hydrophobic receptor with forced wetting


It is an open question if lyophobic receptor site of the self-alignment medium can be used for self-assembly. We investigate this question using both numerical simulation and experimental studies on hydrophobic receptor sites (advancing contact angle of 118°) with superhydrophobic substrate (contact angle of 180° ).


About Aalto University


  • The Micro- and Nanorobotics Group at Aalto University, School of Electrical Engineering, Department of Automation and Systems Technology was started in early 1990s, beginning with micromanipulation. Since then, the research group has carried out numerous research in cell manipulation, microassembly, microforces, microfluidics, paper fiber handling, in vivo diagnostics and nanomanipulation, where both theoretical and experimental methods are used.
  • Currently, the research group is actively working on microassembly, nanomanipulation, mobile robotics and their applications. The research is highly interdisciplinary, merging micro- and nano physics, self-assembly, robotics and automation. With micro- and nanorobotics and self-assembly as the key competence, the research group is actively working hybrid microassembly and their applications in electronics and optoelectronics manufacturing, in-situ nanorobotic testing inside environmental scanning electronic microscope (ESEM), and intelligent microassembly.


Dr. Quan Zhou, Adjunct Professor (Dosentti)