New inks for the direct drop-on-demand fabrication of polymer lenses

• Published in: Microelectronic engineering 2011-08, Vol.88 (8), p.2174-2179
• Main Authors: Voigt, A., Ostrzinski, U., Pfeiffer, K., Kim, J.Y., Fakhfouri, V., Brugger, J., Gruetzner, G.
• Format: Article
• Language: English
• Subjects: Applied sciences; Cameras; Ceramics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electronics; Epoxy resin; Exact sciences and technology; Geometry; Ink; Ink-jet printing; Inks; Lenses; Markets; Materials science; Materials synthesis; materials processing; Microelectronic fabrication (materials and surfaces technology); Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Patterning; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Shape tuning; Sol gel process; Sol-gel; Surface treatment; Surface treatments; Two materials
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2010.12.004

The advent of cell phone cameras extensively pushed market needs for micro lenses and supported developments like the Wafer-Level-Camera Technology [1]. Different optical applications and patterning methods for micro lenses require different sets of materials. Micro ink-jet printing (micro IJP) is an alternative and innovative direct patterning method for the manufacture of micro optical systems. We demonstrate the development of two material compositions – an epoxy resin and a sol–gel based material – which are used as inks with physical parameters adapted to the patterning technique so that stable and reproducible drops in both continuous and drop-on-demand (DoD) mode can be generated. The manufacturing of micro lenses, the lens characterization, their geometry and their optical properties are presented.