US Patent 9512466 Microdroplet formation by wells in a microfluidic device

A method of forming microdroplets is provided that includes forming a well plate, using lithography, where the well plate includes a microchannel and a microwell in a surface of the fluid channel, flowing a first fluid into the microchannel, where the microchannel and the microwell are filled with the first fluid, and flowing a second fluid into the microchannel, where the first fluid is displaced from the microchannel, where the first fluid remains in the microwell, where a microdroplet of the first fluid is formed.