Horizontally Bi-laminating Y-feed Mixing

1 Mixer 29 [M 29] Unfocused Horizontally Bi-laminating Y-feed Micro Mixer 

The material choice and hence the microfabrication was based on the specific needs of Fourier transform infrared (FTIR) spectroscopy, to have IR-transparent materials [110]. For this reason, CaF2 disks are an essential part of the device. The main part of the device consists of two polymer layers sandwiching one metal layer which are encased by the two disks, acting as a kind of end plates. 

In a first step, the negative working photoresist SU-8 is spin-coated on to the disk and soft baked [110]. The disk is then UV-exposed to pattern the bottom layer. A silver thin metal layer is thereafter evaporated. The metal layer is spin-coated with an AZ-type photoresist, dried, exposed and developed. In this way, the metal layer can be developed independently from the patterning of the SU-8 layer underneath. The metal layer is patterned by wet-chemical etching. As a next step, a second SU-8 layer is deposited, soft-baked and exposed. Top and bottom layers are now developed. After a hard bake, a second CaF2 disk is attached to the stack and sealed by a light-curing epoxy resin. 

Mixer type Unfocused bi-lamination micro mixer Metal layer material Silver (evaporated) 

Mixer material Polymer SU-8 Metal layer thickness 2 pm 

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