【作者】 鹿飞；

【导师】 吴伯瑜；

【作者基本信息】 清华大学 ， 电子科学与技术， 2004， 硕士

【摘要】 本论文的主要工作是聚合物电光调制器行波电极系统的研究,包括理论分析、优化设计、工艺制作、微波测试等环节。主要内容包括:(1) 利用聚合物光波导电光调制器仿真计算程序分析评价了 5 种各具特色的电极结构。优化设计出光波长λ=1.319μm,器件互作用区长 20mm 的微带电极聚合物电光强度调制器,其带宽为 39.9GHz,半波电压为 2.275V。 (2) 完成了微带到 CPW 过渡区的设计,解决了横向尺寸几十微米的微带电极到几百微米 CPW 电极的过渡难题,并计算出过渡区详细尺寸和电极性能参数。设计完成双向结构和多分叉结构微带电极掩模版,该结构可大大提高工艺制作成功率。 (3) 在 Si、石英、玻璃衬底上制作了两种类型共 15 片 CPW 电极样片,其中10 片电极的下面有多层聚合物薄膜。所有电极都测试了 S 参量。 (4) 与理论结果相对照,实测 20GHz 石英衬底聚合物 CPW 电极微波等效折射率 Nm=1.689、损耗系数α0 = 0.32dB/(cm GHz) ;40GHzCPW 电极损耗系数α0 = 0.35dB /(cm GHz ),均与理论值相符合。 (5) 用实测 Nm 和α0估算石英衬底 CPW 聚合物电光调制器带宽高于 37GHz,超过 20GHz 的设计带宽,实验证明该种 CPW 电极可以用于本项目的 20GHz 聚合物电光调制器。 (6) 详细分析 Si 衬底 CPW 电极损耗很大的现象,指出原因在于 Si 电阻低产生了大介质损耗,提出可用石英代替 Si 作衬底。 (7) 工艺制作上解决了多层聚合物薄膜旋涂时的侵蚀起泡问题,创建了完整的工艺流程和操作规范,大幅度缩短了多层聚合物薄膜的制作周期,单片制作从一周缩短至几个小时。克服电极电镀中光刻胶漂胶现象,提高了电极制作的成功率。详细研究了在上包层 NOA73 上溅射铬金时出现的纹理现象。将上包层材料 NOA73 改换为与下包层相同的材料。更多还原

【Abstract】 In this dissertation, studies of traveling-wave electrode of polymerElectro-optic modulator, including theoretic analysis, optimizing, design,fabrication and testing, were carried out. The main results include:(1) Five types of electrodes were presented and compared to each other byFEM. The polymer electro-optic modulator with MSL electrode, whichbandwidth is 39.9 GHz and half-wave voltage is 2.275V at wavelength 1.319μmand length of interactive region 20mm, were designed.(2) MSL traveling-wave electrodes of polymer Electro-optic modulator weredesigned. The method of transition from MSL to CPW has solved theconnection between MSL and coaxial connector. Dimensions and performanceparameters of transitional region were computed in detail. For MSL,bidirectional mask and ramose mask were designed respectively. Both maskshave improved the chances of successful fabrication of MSL modulator.(3) Two types of 15 CPW electrodes based on silicon, quartz and glasssubstrates were fabricated, 10 electrodes among which were based on thepolymer layers. All of them were tested for S parameters.(4) According with the theoretic results, tested Nm is 1.689, α0 is0.32dB /(cm GHz) of 20GHz CPW electrodes based on the quartz withpolymer layers, while tested α0 is 0.35dB /(cm GHz) of 40GHz CPWelectrodes.(5) The bandwidth of polymer Electro-optic modulator, which is computedusing tested parameters, is more than 37GHz, exceeding the target 20GHz. Itwas proved that this kind of electrode is fit for the polymer modulator.(6) Tested results have showed that the loss of CPW based on the silicon ismuch more than that on the quartz or glass, for the low resistivity of silicon.The solution would be to use substrate quartz rather than silicon. - II -<WP=5>(7) The total fabricating process has been created and developed. Thedissolution between polymer layers has been solved. The fabricating period hasbeen reduced to several hours from about a week. It has been solved thatphotoresist would fall off the golden electrode during the electroplating process.The problem that cladding layer NOA73 would crack during the sputteringprocess has been also analyzed. BPAN/M20S has replaced NOA73 as claddingmaterial.更多还原