The measurement of local temperatures under micro jet impinging using HFE-7000.

Experiments were conducted to understand temperature distribution and measure local heat transfer coefficients under micro scale jet impinging using a refrigerant, HFE-7000 from 3MTM. The device used in the experiment was made of a 400 μm thick silicon wafer, a 500 μm thick Pyrex substrate, and a 250 μm thick vinyl sticker. On a silicon wafer, jet orifices were etched using deep reactive ion etching (DRIE). A heater and four 100 nm thick titanium resistance temperature detector (RTD) thermistors were fabricated on the Pyrex wafer. Between the Pyrex and silicon wafers, the vinyl sticker including a 1.9 mm × 14.8 mm × 0.25 mm micro channel was located to make them together. From the experiment, local temperatures from four RTDs were measured by heat fluxes at a flow rate, and local heat transfer coefficients were estimated to understand the characteristics of the jet impinging cooling.