本研究計畫目的在於開發一個新型的光學監控系統,可同時擷取反射自薄膜的監控光之強度和反射相位變化。此系統將利用新型動態新型偏振干涉儀去抑制機械震動和消除空氣擾動的干擾,即時計算出沉積中的膜堆在每一刻的反射係數、光學導納、折射率和厚度的解析解,提供一個直接且全面性的監控方式。以往的光學監控方式在製鍍光學薄膜的過程中,因為只有光在強度上的監測而缺乏光在垂直方向上的相位量測,無法清楚區分折射率的變化和厚度的變化,以致於沒辦法做精確的製程掌控,如製在鍍雷射線濾光片(Laser Line Filter)、高密度波長多工器(DWDM)等精密等等的薄膜元件時,良率不高、成品價格昂貴。本計畫的重點即在發展一突破性的光學監控方法以解決這個長久以來的難題,並搭配光學導納軌跡之觀測做即時性膜層厚度錯誤補償。導納軌跡常被應用於濾光片之初始設計,以及製鍍膜層厚度有錯誤時的補償分析。因其同時具有光的電場強度和相位之資訊,本研究可藉由單一參考波長之導納軌跡之分析,即可維持整個光譜之正確性,保障濾光元件之成品能符合設計之光學成效(Optical Performance)。相較於近期國際發展的各式新型監控法,本架構毋須經由單一轉折點光強資訊推算導納軌跡,再回推停鍍點的穿透率,亦毋須設定各層折射率不會隨厚度變化的錯誤假設。本架構將可觀測各時刻折射率和厚度的二維分佈變化,這是傳統光學監控系統無法企及的,而這項特點將有助於學術領域中對於不同製程參數和材料之薄膜在成長中微觀結構變化機制的研究。導納軌跡監控對於四分之一波堆的製鍍有特別高的靈敏度,且靈敏度有隨著膜層增加而增長之特性。本研究將可避免目前一般用於製鍍四分之一波厚多層膜的窄帶濾光片之極值監控方法在每層切點處靈敏度特別低的缺點,可大幅降低厚度誤判之機率,改進雷射線濾光片、高密度波長多工器等精密濾光原件之製鍍良率,對於學術或產業界都將具有很大的價值。 A novel monitor system will be developed in this project to extract the real-time reflection phase and magnitude of monitoring light coming from a growing thin film stack. A new-type dynamic polarization interferometer will be applied in the system to erase the mechanical vibration and air turbulence effect and obtain the reflection coefficient, optical admittance, refractive index and thickness at every moment. It provides powerful and global monitoring for optical coatings. In conventional monitors, only light intensity is monitored, but the optical phase cannot be observed, so that neither refractive index nor thickness can be known. Therefore the deposition process is not able to be precisely controlled resulting in the low yield efficiency of some optical elements, such as laser line filter, DWDM, etc. This project is going to build a new monitoring system to solve this long-time problem, and implement an optical admittance loci monitor analysis to have an error compensations scheme. Optical admittance loci are generally applied in filter designs and error compensations calculations in coating production. Since they have intensity magnitude and optical phase information, by analyzing the optical admittance of one single reference wavelength, we can keep the whole output spectrum satisfy what we have designed. Unlike other recently developed monitoring method, in our monitor system, optical admittance is not acquired from tuning points of transmittance curve under the incorrect assumption, such as refractive index is constant, and is not necessary to be converted back to transmittance. The variations of refractive index and thickness in monitoring area at every moment can be observed in this system. This would greatly help the understanding of thin film growth mechanism. Optical admittance locus monitor has high sensitivity on manufacturing a quarterwave stack, and the sensitivity increase as layer number increase. It avoids the major defect when using the conventional turning point monitor in which sensitivity become poor in quarter-wave stack fabrication. Therefore, the monitor method in this project would greatly improve the control precision and decrease the cost for the production of sophisticate optical filters. 研究期間:10008 ~ 10107