Electrospray emitter for microfluidic channel

5 The electrospray device of claim 3 wherein the tip of the emitter film has an apex angle of approximately 90 degrees.

A method of making an electrospray device, the method comprising:

• forming a microchannel on a substrate running to an edge of the substrate;
• obtaining a thin film emitter having a body portion with a polygonal tip on an edge of the body portion;
• bonding the substrate and a cover with at least part of the body portion of the thin film emitter between the substrate and cover such that the tip extends from the channel at the end of the edge of the substrate.

An electrospray device comprising:

• a chip having a covered microfluidic structure that delivers fluid to an edge of the chip;
• and
• an emitter having a tip coupled to the edge of the chip and extending therefrom, wherein the tip has an apex shaped to facilitate formation of a Taylor cone from fluid delivered to the edge of the chip.