Analysis of Surface Structure of Organic Molecules by Scanning Probe Microscope (SPM)

1. 聚合物薄膜的原子力显微镜图像：采用准分子激光烧蚀技术对具有代表性的导电聚合物聚噻吩薄膜进行了微图像化处理。将厚度为0.3 μ m的聚噻吩薄膜转移到石英板上，用准分子激光通过掩膜照射。用原子力显微镜（AFM）估计了图案的分辨率，当膜被ArF激光（193 nm）照射时，图案的分辨率在微米数量级。同样的实验也应用于可溶导电聚合物聚烷基噻吩薄膜的微图图化。有机薄膜的原子力显微镜图像：(1)用原子力显微镜观察了空气和水中花生酸单分子膜转移到玻璃板上的情况。在水中观察到的图像清晰且具有分子分辨率，而在空气中观察到的图像有噪声且不稳定。这可能是因为悬臂杆和单分子膜之间的粘附作用在水中比在空气中弱。(2)用原子力显微镜（AFM）跟踪了聚二乙炔a型和b型薄膜之间的相变。每层厚度随着相变的发生而减小，这是由于分子的堆积性得到了改善。(3)利用原子力显微镜估计了硅烷偶联处理后玻璃板低能固体表面的附着力，并与固体表面的接触角进行了比较。讨论了附着力与接触角的关系。用扫描隧道显微镜（STM）观察了溶剂铸造法制备的聚γ -苄基-谷氨酸（Poly - gamma-苄基- l-谷氨酸）薄膜在磁场中的STM图像。发现不同分子取向区域之间存在明显的相边界。

1. AFM images of polymer films : Excimer laser ablation was applied to the micropatterning of thin films of polythiophene which is a representative conducting polymer. A polythiophene film of 0.3 mum thick was transferred onto a quartz plate and was irradiated by an excimer laser through a mask. The resolution of the patterning was estimated with an atomic force microscope (AFM) and was of the order of micrometer when the film was irradiated by an ArF laser (193 nm). The same experiment was applied to the micropatterning of thin films of poly (alkylthiophene) which is a soluble conducting polymer.2. AFM images of organic films : (1) Arachidic acid monolayrs transferred onto a glass plate were observed with the AFM both in air and in water. The images observed in water was clear and had molecular resolution, while the images observed in air were noisy and unstable. This is probably because the work of adhesion between the canti-lever and the monolayrs is weaker in water than in air. (2) Phase transition between the A-and the B-type of polydiacetylene films was traced with the AFM.The thickness per layr decreased with the phase transition, which is ascribed to the improvement of the packing of the molecules. (3) Adhesion force for the low energy solid surfaces formed by a silane coupling treatment of glass plates was estimated with the AFM and was compared with the contact angles of the solid surfaces. The relationship between the adhesion force and the contact angle was discussed.3. STM images of polypeptides : Poly (gamma-benzyl-L-glutamate) films prepared by the solvent cast method in the magnetic field were observed with a scanning tunneling microscope (STM). A manifest phase boundary between the regions with different molecular orientations was found.