A dispenser for chemical fluid samples that need to be precisely ejected in size, location, and time. The dispenser is a micro-electro-mechanical systems (MEMS) device fabricated in a bonded silicon wafer and a substrate, such as glass or silicon, using integrated circuit-like fabrication technology...http://www.google.co.uk/patents/US5877580?utm_source=gb-gplus-sharePatent US5877580 - Micromachined chemical jet dispenser
