有機-無機光敏感性積體光學材料

Abstract

本實驗利用化學醯亞胺法 (chemical imidization) ，成功合成出光敏感性醯亞胺寡聚物PSI (photosensitive imide)。並利用溶膠凝膠法 (sol-gel) 改質無機SiO2顆粒，使其表面帶有壓克力基之改質矽MS (modified silica)。將PSI、MS與壓力克母體TEGDA (tetraethylene glycol diacrylate)，以特定的比例混合，加入光起始劑 Irgacure 651 (2,2-dimethoxy-2-phenyl acetophenone)，真空除掉溶劑後，即得光波導蕊層 (croe) 及披覆層 (cladding) 之有機-無機光敏感性積體光學材料。其中蕊層材料的配方則分為 (1) P系列 : 固定有機組成和無機組成在材料內部的含量，但改變有機組成中PSI與壓克力母體TEGDA的比例，TP00-S40、TP05-S40、TP10-S40及TP20-S40。(2) S系列 : 固定有機組成中PSI與TEGDA的比例，但改變有機組成與無機組成的比例，TP20-S00、TP20-S10、TP20-S20及TP20-S40。 為了性質量測的方便，將有機-無機光敏感性積體光學材料利用成型帶 (mylar film) 壓蓋、模具澆鑄和光罩微影方式，照以波長365 nm之UV光，則分別得到薄膜、藥錠及光波導元件樣品。然後，使用儀器UV-Vis-NIR光譜分析儀、microscratch薄膜分析儀和prism coupler，量測薄膜樣品光穿透度 (在波長850 nm、1310 nm、1550 nm)、微刮力及折射率。儀器TGA、DSC、TMA和微硬度儀，量測藥錠樣品的熱裂解溫度Td、玻璃轉移溫度Tg、熱膨脹係數CTE及硬度。另外也量測了藥錠樣品的吸溼性。儀器光傳損失分析儀，量測光波導元件在通訊波長1310 nm及1550 nm之光傳損失 (optical loss)。 結果顯示，本實驗所開發出有機-無機光敏感性積體光學材料，其光穿透度>95%、光傳損失<2 dB/cm、圖案解析度<5μm、熱裂解溫度>350℃及吸溼性<5 wt%。

The goal of this research is to develop photosensitive organic-inorganic hybrid materials for integrated optics. The hybrid materials possess some properties, like soventless, UV-curable, higher thermal decomposition temperature, and low optical loss. In this research, the photosensitive imide (PSI) was synthesized by chemical imidization from functionalized fluorinated dianhydride 6FDA [4,4′-(Hexafluoroisopropylidene)diphthalic anhydride] and dianiline 6FpDA [4,4'-(Hexafluoroisopropylidene) dianiline]. The PSI molecular structure has multi-reactive- unsaturated functional groups (-CH=CH2). It can be polymerized with the acrylate matrix, TEGDA (Tetraethylene glycol diacrylate), by free radical polymerization. In addition, the modified silica (MS) nano-particle was synthesized by sol-gel processes. The MS particle size was 20-25nm, and the surface of MS was modified with MPS (3-Methacryloxypropyl Trimethoxy silane). By mixing organic components, PSI and TEGDA, inorganic components, MS, and photoinitiator with particular weight ratio, then the photosensitive organic-inorganic hybrid materials, core materials and cladding materials for optical waveguide, were obtained. In order to study the effects of the content of PSI and MS in materials upon the physical properties, especially optical properties, core materials were divided into two parts, P series and S series. P series were that fixing the weight ratio of organic components and inorganic components in materials, but changing the weight ratio of PSI and TEGDA in organic components. P series formulas were TP00-S40, TP05-S40, TP10-S40, and TP20-S40. S series were that fixing the weight ratio of PSI and TEGDA in organic components, but changing the weight ratio of organic components and inorganic components in materials. S formulas were TP20-S00, TP20-S10, TP20-S20, TP20-S40. In order to measure materials’ properties conveniently, the thin film, tablet and optical waveguide device samples were made. The properties of optical transmittance (at 850nm, 1310nm and 1550nm), microscratch force and refractive index of thin film core materials were evaluated by UV-Vis-NIR spectrum, Microscratch, and Prism Coupler respectively. The properties of thermal decomposition temperature (Td), glass transition temperature (Tg), coefficient of thermal expansion (CTE), and hardness of tablet core materials were evaluated by Thermogravimetric Analyzer, Thermomechanical Analyzer, and Hardness tester respectively. The properties of optical loss of optical waveguides were also evaluated by optical loss instrument that consists of laser sources, power meter, and power detector like Fig. 20. Photosensitive organic-inorganic hybrid materials, TP20-S40, exhibit optical transmittance > 95% (at 850nm, 1310nm, and 1550nm), optical loss < 2dB/cm (at 1310nm and 1550nm), pattern resolution < 5μm, Td > 3500C, and water absorption <5 wt%.