Temperature measurements of heated microcantilevers using scanning thermoreflectance microscopy

Abstract

We report the development of scanning thermoreflectance thermometry and its application for steady and dynamic temperature measurement of a heated microcantilever. The local thermoreflectance signal of the heated microcantilever was calibrated to temperature while the cantilever was under steady and periodic heating operation. The temperature resolution of our approach is 0.6 K, and the spatial resolution is 2 μm, which are comparable to micro-Raman thermometry. However, the temporal resolution of our approach is about 10 μsec, which is significantly faster than micro-Raman thermometry. When the heated microcantilever is periodically heated with frequency up to 100 kHz, we can measure both the in-phase and out-of-phase components of the temperature oscillation. For increasing heating frequency, the measured cantilever AC temperature distribution tends to be confined in the vicinity of the heater region and becomes increasingly out of phase with the driving signal. These results compare well with finite element simulations.

Measuring the surface temperature of light-emitting diodes by thermoreflectance

“…Figure 1 depicts the schematic TR experimental setup used in this study. [16][17][18] A probe laser beam with a wavelength of 532 nm (Coherent OBIS 1261777), which is highly sensitive to the temperature change in Au film, is modulated by a function generator and focused on a metal electrode of the LED sample through a microscope objective lens (100×). The diameter of the laser spot on the electrode of the LED surface is ∼3.0 μm.…”

Electrothermal Characterization of Doped-Si Heated Microcantilevers Under Periodic Heating Operation

“…However, understanding the full spectrum 3ac signal of the doped-Si heated cantilever still remains challenging, mainly due to the inherent complexities of the cantilever, such as the presence of two doped regions, a nonlinear temperature dependence of the cantilever resistance, and the complicated geometry. While previous studies have attempted to predict the ac behaviors of the microcantilever with a simple 1D model [38,39,[49][50][51][52][53], they observed serious deviations of the 1D model from experimental data at high frequencies [51,52]. FEA was applied for the transient modeling of the cantilever during pulse and periodic heating operations [54].…”

High-speed thermoreflectance microscopy using charge-coupled device-based Fourier-domain filtering

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