聚二甲基矽氧烷(PDMS)微懸臂樑結構在生物細胞、活細胞、與軟性材料的奈米機械量測領域可是非常有用的，因此為了快速得知聚二甲基矽氧烷材料的機械特性，我們提供了利用多層次軟性微影的方法製作聚二甲基矽氧烷微懸臂樑，並且量測其熱噪聲，再由熱噪聲的量測可得知聚二甲基矽氧烷材料依造不同比例混的楊氏係數，我們量測聚二甲基矽氧烷微懸臂樑共振頻與品質因子的範圍分別在405 Hz到1.63 kHz與5~10，且經過我們的計算，我們聚二甲基矽氧烷微懸臂樑的彈性常數~10-4 N/m，比一般商品化原子力顯微鏡微懸臂樑小100倍甚至更小，且最小力量解析度大約在皮牛頓的範圍，因此我們未來可以利用它來量測生物力學，甚至可做到單分子細胞生物力學的量測。

Polydimethylsiloxane micro structures such as cantilevers have been shown useful for nanomechanical measurement of biomolecules, living cells, and soft matter. As a fundamental characterization, we report the thermomechanical noise measurement of flextual modes of polydimethylsiloxane cantilevers, fabricated multilayer soft-lithography. From the resonance frequency data, we extract the values of Young’s moduli for different cross linking ratios. Our devices have measured resonance frequencies and quality factor ranging from 405 Hz to 1.63 kHz and from 5 to 10. The spring constants is ~10-4 N/m, 100 times smaller than commercially available atomic force microscope cantilever and the force resolution is in the pico newton range. Our experimental data and analysis show that such cantilevers will be capable of performing the nanomechanical measurement at single molecular level.

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