2011YTC

陳禹同 (Yu-Tong Chen)

Fabrication of sealed microchannels by permeated and double-side partial exposure method

以滲透法及雙面部分曝光製作封閉型微流道

A novel process was proposed to fabricate sealed micro channels by using negative photoresist SU-8, preciously in our lab, which needs only single-layer coating of and double-side partial exposure to have non-uniform inside cross section. However SU-8 cross-linked effect from double-side exposure mede it difficult to have channels height less than the 100μm, and channels length longer than 400μm length.

According to Yoshikazu Hirai’s paper, different post-exposure bake (PEB) temperature, SU-8 will affect the cross-linked effect as well as permeability , so-called semi-cross-linked, when PEB temperature at 85℃ was suggested to increase channel length. Here by combine semi-cross-linked and double-side partial exposure method on SU-8, a fabricate scheme is proposed to fabricate sealed micro channels having non-uniform inside cross section at long channel length and thinness channel height.

From experiment results, it is shown that the micro channels length can be increased from 200μm to 2000μm, for the channels height can be reduced from 400μm to 100μm by the process method. Ot is alse found that 10mJ only to single exposure of SU-8 on one side, double exposure will increase the thickness of developed SU-8 about 8%, even at the same total dosage of 30mJ. Finally, a feasible recipe is established to successfully fabricate sealed micro channels with variable inside cross section, and longer channels length and thiness channels height.