Ink-Jet Fabrication of Polymer Microlens for Optical-I/O Chip Packaging

Abstract

We report on a simple and versatile method of fabricating polymer microlenses that can be easily integrated with optical devices. UV-curable epoxy resin is dropped onto optical devices by an ink-jet apparatus. When the droplets touch the surface, they form into partial spheres due to their surface tension. UV light irradiation for less than five minutes can easily turn them into solid microlenses. Various microlenses, having a geometrical diameter from 20 to 140 µm with F/1.0 to F/11.0, were successfully produced by controlling the volume and viscosity of the polymer resin and their wettability to the substrate. Their uniformity in a microlens array was measured to be within ±1% in diameter and ±3 µm in pitch. Hybrid integration of an ink-jetted microlens with a wire-bonded vertical-cavity surface-emitting laser (VCSEL) was also demonstrated. When an inkjetted microlens (45-µm diameter, F/2.0) was formed on the aperture of an 850-nm VCSEL, the coupling efficiency into a single-mode fiber was 4 dB higher than without the microlens.

Diffuse Interface Modeling of Droplet Impact on a Pre‐Patterned Solid Surface

“…In addition, since printing patterns are digitally generated, it is a flexible process. To utilize these advantages, recently efforts were focused on making ink-jet printing a viable technique for manufacturing a range of different functional materials and devices, for example, thin film transistors, [1,2] DNA microarrays, [3] light-emitting diodes, [4,5] micro-lens, [6] and others. [7,8] Functional materials and devices are used in existing and emerging applications in diverse fields such as microelectronics, optoelectronic, biomedics, ceramics, and so on.…”

Fabrication of Microlens Array and Its Application: A Review

“…Microdroplet jetting, also known as ink jet printing, is another direct method for fabricating microlenses [38][39][40][41][42]. Figure 6 shows a schematic diagram of the working principle of this method [39].…”

Biomimetic Multiaperture Imaging Systems: A Review

“…Removing the top patterned electrode resulted in a microlens array on the nonpatterned electrode. In addition, E-beam lithography, (31) ink-jet fabrication, (32,33) a photothermal technique using photosensitive glass, (34) optically induced volume changes in recording materials, (35)(36)(37) hot embossing, (38) laser lithographic fabrication, (39) soft lithography, (40) and a hybrid sol-gel method (41) have all been used to fabricate microlens arrays.…”