| 摘要 |
A method and apparatus for rapid temperature changes of thin samples is disclosed. The apparatus comprises of a thin-film resistive element embedded in a membrane, a narrow gap between the membrane and a heat sink, and a control circuit. The resistive element acts both as a heater and as a temperature sensor to reduce time constant of the control circuit. The gap between the membrane and the heat sink is filled with gas (e.g., N2 or He) acting as cooling medium with low thermal inertia. The temperature controller has a microsecond time constant, which allows adjusting rapidly the power applied to the membrane, depending on heat released/absorbed by a sample during an isotherm or during a given rate of temperature changes. The membrane has low thermal inertia and, coupled with high-speed temperature controller, allows controlled cooling and heating rates up to 100 000 K s-1 and higher. The method can be a core of any setup where controlled fast temperature-time profile of thin or small sample is desirable. The proposed control circuit can be readily applied to the variety of the existing setups with resistive heater.
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