有机半导体横向热扩散率的频变光热测量
Frequency-Dependent Photothermal Measurement of Transverse Thermal Diffusivity of Organic Semiconductors
摘要：
我们已经使用了光热技术，其中斩波光加热的前表面的一个小的（~ 1 mm 2）样品和斩波频率依赖性的热辐射从背面测量与液氮冷却的红外探测器。在我们的系统中，样品直接放置在杜瓦瓶内的检测器前面。因为检测器对在样品周围或通过样品泄漏的一些入射光也敏感，所以对与斩波光正交的检测器信号进行测量。结果呈现为层状晶体的半导体6，13-双（三异丙基甲硅烷基乙炔基）并五苯（TIPS-PN）和纸的纤维素纳米原纤维涂覆有半导体聚（3，4-乙烯-二氧噻吩）：聚（苯乙烯-磺酸盐）（NFC-PEDOT）。对于NFC-PEDOT，我们已经发现，横向扩散率，小于面内值，与厚度成反比，这表明纸的纹理随厚度而变化。对于TIPS-pn，我们已经发现，层间扩散率是一个数量级大于面内值，与以前的估计一致，这表明低频光学声子，大概与TIPS侧群中的振动，携带大部分的热量。
英文摘要：
We have used a photothermal technique, in which chopped light heats the front surface of a small ( ~ 1 mm2) sample and the chopping frequency dependence of thermal radiation from the back surface is measured with a liquid nitrogen cooled infrared detector. In our system, the sample is placed directly in front of the detector within its dewar. Because the detector is also sensitive to some of the incident light which leaks around or through the sample, measurements are made for the detector signal that is in quadrature with the chopped light. Results are presented for layered crystals of semiconducting 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pn) and for papers of cellulose nanofibrils coated with semiconducting poly(3,4-ethylene-dioxythiophene):poly(styrene-sulfonate) (NFC-PEDOT). For NFC-PEDOT, we have found that the transverse diffusivity, smaller than the in-plane value, varies inversely with thickness, suggesting that texturing of the papers varies with thickness. For TIPS-pn, we have found that the interlayer diffusivity is an order of magnitude larger than the in-plane value, consistent with previous estimates, suggesting that low-frequency optical phonons, presumably associated with librations in the TIPS side-groups, carry most of the heat.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
