US Patent 9207540 Integrating functional and fluidic circuits in joule-thomson microcoolers

A method includes etching one or more fluidic channels into a first substrate made of a first material according to a first spatial pattern. The method also includes, after etching the fluidic channels, then separately etching a space in the first substrate according to a different second pattern that includes at least one connection between at least two different portions of the fluidic channels. The method still further includes depositing a different second material into the space. The method yet further includes bonding a different second substrate to the first substrate to enclose the fluidic channels to configure them to contain or pass one or more fluids. For fabricating a Joule-Thomson cooler, the first substrate is made of a first thermally insulating material; the second material is a thermally conducting material; and the second substrate is made of a second thermally insulating material.