【作者】 李明亮；

【导师】 李峰；

【作者基本信息】 吉林大学 ， 物理化学， 2013， 硕士

【摘要】 自1960年世界上第一台激光器诞生以来，激光技术得到空前的发展，满足了其它许多行业的各种需求，对推动信息技术的前进起到了重要作用。时至今日，激光的应用已经渗入到我们的日常生活中，然而我们目前应用的激光技术主要建立在无机材料基础之上，传统的无机材料性质稳定，基础理论和加工工艺都已经非常成熟，但是无机材料中的重金属元素对环境不友好，而且属于稀缺资源，寻找替代材料是传统产业向新兴产业过渡所必需的。有机发光材料作为新兴的研究热点，近年来得到迅速发展，从白光OLED照明到OLED的彩色显示，有机材料正在像当年的无机半导体材料一样逐渐融入我们的生活，激光作为我们日常工作和生活中不可或缺的部分，却仍然没有出现可代替的有机部分。有机半导体激光器一直是激光领域中的热点与难点，事实上有机激光的研究历史几乎与激光器的历史一样长，从染料溶液发光到染料掺杂固态发光，再到后来的有机聚合物，有机材料也在向前发展，人们已经实现了光泵浦条件下的有机半导体激光。但是从应用的角度来讲，光泵浦的有机激光还无法投入商用市场，如何实现电注入条件下的有机激光是当前激光领域亟待攻克的难题。我们的实验从激光的谐振腔角度出发，采用分布反馈(DFB)的谐振腔结构，和其它常见的谐振腔结构相比，这种结构被证明更容易降低激光阈值，而且对激光的选模作用较好。我们用双光束干涉法在玻璃基底上制作SU8的光栅结构，SU8作为一种负胶，其结构稳定，可长期使用。增益介质我们选用2,5,2＇,5＇-tetrakis(2,2-diphenylvinyl)biphenyl(TDPVBi)，TDPVBi作为一种小分子材料，其在蒸镀时成膜质量好，发光效率高，我们将TDPVBi蒸镀到DFB结构之上，然后用波长为355nm的脉冲激光源泵浦器件，观测器件的边发射光谱。我们制作了不同周期的DFB结构，在这些不同的周期结构上又蒸镀不同厚度的TDPVBi薄膜，通过优化DFB的周期和有机层的厚度，我们实现了基于SU8光栅结构的激光，通过论证和实验分析我们得出结论：这是一种特殊漏模模式下的DFB激光，特殊漏模模式也可以称之为截止模，这种模式的优点是光损耗小，而DFB可以对激光的出射起到选模的作用。我们制作DFB激光的方法简单，只需在玻璃基底通过双光束干涉曝光就可以制得DFB结构，这和之前人们在Si基底上刻蚀光栅相比，工艺简化许多，并且得益于截止模模式的低损耗，激光的阈值还有很多的下降空间，这为将来实现电注入有机激光开辟了新的思路。更多还原

【Abstract】 Since the first laser was invented in1960, laser’s technology has been developedgreatly. The laser satisfies various requirements of other industries and it plays animportant role in the information technology. Today, the applications of laser havepermeated our daily life. However the lasers we used are all founded on the inorganicmaterials which have stable property. Their basic theories and processing technologiesare very mature. But the metallic elements of inorganic materials are harmful toenvironment, and some of them are scarce resources. As a new area of research,organic light-emitting materials have developed rapidly recently. Just like inorganicmaterials, organic light-emitting materials blend in our life gradually.Organic semiconductor laser has been hotspot in the area of laser. In fact theresearch history of organic laser is almost as long as lasers. It experienced three stages:dye solution laser, dye doped solid laser and polymer laser. People have realized laseremission from organic semiconductor under optical pump. In term of application, thelaser under optical pump could not be commercialized. How to realize laser underelectrical pump is still a problem.Our research selects distributed feedback(DFB) structure as the resonator.Compared with other structures, DFB has been demonstrated that it could decreasethreshold of laser easier, and it has mode selective function. We fabricate gratings ofSU8on the glass substrates by dual beam interference. As a kind of negativephotoresist, SU8has table physical property, so it could be used in a long time. Wechoose2,5,2’,5’-tetrakis(2,2-diphenylvinyl)biphenyl (TDPVBi) as gain medium.TDPVBi is a kind of small molecular materials which has high luminous efficiencyand good quality of film. We evaporate the TDPVBi onto DFB structures and pump itwith pulse laser whose wavelength is355nm, andthen observe the spectra fromedge-emission. We fabricate gratings with different periodsand evaporate differentfilm thickness of TDPVBi onto the gratings. By optimizing the grating period andfilm thickness, we realize laser based on SU8gratings. It should be a kind of DFB laser based on special leaky mode which could also be called cutoff mode. This modehas advantage of low optical loss, and the DFB resonator plays the role of modeselection.Compared with etching gratings on Si substrates, our DFB laser could be simplyprocessed. And threshold of DFB laser still have possibility of decrease benefitingfrom the low optical loss in cutoff mode. This presents a new idea for realizingelectrically pump laser.更多还原