microdispensing

Microdispensing is the controlled deposition of very small volumes of liquid, typically in the picoliter to microliter range, onto a substrate with high repeatability. It is used to apply precise amounts of adhesives, solder pastes, resins, biological reagents, and other functional fluids in manufacturing, electronics, medical devices, and research. Systems are automated and often integrated into production lines or lab workflows.

The core technologies include nozzle-based and valve-based dispensing. Nozzle-based systems use actuators such as piezoelectric or thermal printheads to eject droplets through a microchannel and nozzle, while valve-based systems regulate flow through a microvalve. Both can be arranged in single-nozzle or multi-nozzle arrays to print patterns or create microstructured deposits. Positioning stages and software control the deposition pattern with micron-level accuracy; typical volume control can be in the nanoliter to microliter range depending on fluid properties.

Applications include electronics assembly (glue dotting, die attach, solder paste deposition), optoelectronics and photonics (patterned adhesives and resin filling), and biomedical uses (droplet-based assays, micro-dosing of reagents, cell-friendly dispensing, and lab-on-a-chip fabrication). Microdispensing enables rapid prototyping and batch production with reduced waste and material use.

Key challenges include fluid properties such as viscosity and surface tension that influence jetting, nozzle clogging, evaporation, cross-contamination, and substrate interactions. Achieving uniform depositions on curved or textured surfaces requires careful process development, fluid conditioning, and environmental control. Routine maintenance, cleaning, and system calibration are essential to sustain accuracy.