p-Si(110)衬底上蒸发生长PTCDA薄膜的生长方式的XRD表征

XRD Characterization of PTCDA Thin Films Grown by Evaporation on p-Si(110) Substrate

我们用XRD对p-Si(110)衬底上蒸发沉积的不同厚度的PTCDA薄膜进行了性能表征。XRD测试结果表明PTCDA在p-Si(110)面上均以晶体方式生长。随蒸发时间变化,即随着PTCDA薄膜的厚度增加,在生长的薄膜中出现了α型和β型两种并存的PTCDA。不同衬底温度下生长的PTCDA薄膜的生长方式为α、β型的共存的PTCDA。生长的PTCDA薄膜都是以晶体形式存在。衬底生长温度为50℃的样片衍射峰大约在2θ ≈ 27.5。衍射峰的位置对应于单斜晶系的(102)晶格平面,此时PTCDA分子平面几乎平行于衬底。生长温度为100℃的样片,PTCDA分子几乎垂直于表面生长。生长温度为150℃的样片与生长温度为100℃的样片其生长方式几乎完全相同。温度为150℃的样片衍射峰强度减小可能归因于在某些区域分子平面相对于衬底平面发生改变。随着温度的升高峰的位置有0.1增加,这归因于β型PTCDA比例的增加。

We characterized the properties of PTCDA films with different thickness evaporated on p-Si(110) substrate by XRD. XRD results show that PTCDA grows in crystal mode on p-Si(110) plane. With the change of evaporation time, that is, with the increase of the thickness of PTCDA film, there is a phenomenon in the grown film α Type and β Type two coexisting PTCDA. The growth mode of PTCDA films grown at different substrate temperatures is α, β Type coexisting PTCDA. The grown PTCDA films exist in the form of crystals. The diffraction peak of the sample with sub-strate growth temperature of 50˚C is about 2θ ≈ 27.5. The position of the diffraction peak cor-responds to the (102) lattice plane of the monoclinic system, and the PTCDA molecular plane is almost parallel to the substrate. When the growth temperature was 100˚C, PTCDA molecules grew almost perpendicular to the surface. The growth mode of the sample with the growth tem-perature of 150˚C is almost the same as that of the sample with the growth temperature of 100˚C. The decrease of diffraction peak intensity at 150˚C may be due to the change of molecular plane relative to substrate plane in some regions. As the temperature rises, the position of the peak increases by 0.1, which is attributed to β proportion of PTCDA increased.