2012-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/714068摘要：本計畫將研發創新的矽波導製程，以均質化的氟-氪準分子雷射照射脊狀結構，並以高溫氧化生長表面的二氧化矽被覆層，可在矽基板上製作出高效能的圓形剖面波導。由於矽材料具有高折射率，並能夠與發展成熟的CMOS製程相容，因此透過此製程預期能在晶片上製作低成本、小尺寸，具有高傳輸效能的光學連結元件。相較之下，現有的電子傳輸匯流排無論在功率損耗、傳輸速度和頻寬等方面，在高頻率的傳輸下都受到銅導線的材料限制；種種不利的因素傳達了發展光子連結的重要性。　 基於現有的研究基礎，本年度的研究計畫可以分成三個部分。首先，我們使用準分子雷射重整以及高溫氧化法對矽鰭狀結構進行結構重整和表面氧化，以在矽基板上直接製作圓形剖面的矽核波導。以此方法製作的矽波導核心直徑可達340奈米，且氧化矽包覆層可使波導與基板隔離。 其次，為了降低液態矽重整時因Plateau–Rayleigh 不穩定性導致的波浪起伏，我們進一步尋找降低結構起伏的方法。透過調整入射的雷射能量與角度，我們可以改變雷射重整時，熔化的矽結構範圍，以保留結構中心的方式，利用表面張力來降低波浪起伏的現象。另一方面，本實驗室亦提出使用氧化矽模具輔助雷射重整製程之方法。透過製程相容的氧化矽模具，可以限制結構的重整區域，亦可調整矽核波導與矽基板之間距，並減輕結構的波浪起伏現象。 高解析度穿透式電子顯微鏡(High-resolution transmission electron microscopy, HR-TEM)在計畫中亦被應用於觀察波導結構，以驗證波導在雷射重整後的單晶性。由觀察結果可以證明，在雷射重整後的結構仍然會維持與基板一致的結晶性。除此之外，為瞭解雷射重整的機制，本實驗室更以數據模擬方式，對二維矽鰭狀結構在雷射重整時的傳熱機制，以及結構熔化重整的過程提出解釋並進行進一步的探討。 <br> Abstract: This project will focus on a novel fabrication method and study of silicon waveguides. By applying homogenized KrF excimer laser treatment and thermal oxidation on silicon ridge structures, round-profile silicon waveguides with SiO2 cladding can be fabricated directly on non-SOI silicon substrate. Because of the high refractive index of silicon and mature CMOS fabrication technology, it is highly anticipated that this method is capable of building on-chip optical interconnection with low cost, small footprint, and high transmission performance. Conventional copper interconnect, in comparison with optical one, has limited performance due to the issues of power dissipation, propagation speed, and bandwidth at high frequency. This disadvantage motivates our further research on optical interconnect. Based on previous result of the project, the research consists of three parts. First, excimer laser treatment, along with thermal oxidation, is carried out in order to reshape silicon fin structure as well as oxidizing surface and neck region of fabricated silicon waveguide. By achieving this, an isolated round-profile silicon core waveguide with a diameter of 340nm can be fabricated. Second, to reduce wavy fluctuation resulted from Plateau–Rayleigh instability during laser treatment, two viable methods are further studied. By modifying incident angle and pulse energy of excimer laser, we can alter the melted region during laser treatment; by achieving this, surface tension of liquid silicon could be utilized to reduce the fluctuation. Also, an alternative solution of oxide-mold-assisted method is presented in this research. By applying this method which is compatible with our current fabrication process, oxide mold could be placed, which thus confines the deformed region of Si fin structure, reduces the fluctuation, and modifies the gap height between Si core waveguide and Si substrate. To verify the crystallinity of reshaped silicon structure, high-resolution transmission electron microscopy (HR-TEM) is applied. It is further proved that the monocrystallinity of the restructured silicon region remains the same as Si substrate. In addition, thermal simulation for two-dimensional silicon fin structure is carried out in order to better understand the reformation mechanism of laser treatment, as well as to explain the shape evolvement during melting process.矽光子元件矽波導光電整合元件積體光學準分子雷射反應式離子蝕刻側壁粗糙度降低Silicon photonicssilicon waveguideoptoelectronic integrated deviceoptical integrated circuitexcimer laserreactive-ion etchingsidewall roughness reduction