Lipka Timo, Moldenhauer Lennart, Müller Jörg, Trieu Hoc Khiem
Opt Express. 2015 Jul 27;23(15):20075-88. doi: 10.1364/OE.23.020075.
Large-scale integrated silicon photonic circuits suffer from two inevitable issues that boost the overall power consumption. First, fabrication imperfections even on sub-nm scale result in spectral device non-uniformity that require fine-tuning during device operation. Second, the photonic devices need to be actively corrected to compensate thermal drifts. As a result significant amount of power is wasted if no athermal and wavelength-trimmable solutions are utilized. Consequently, in order to minimize the total power requirement of photonic circuits in a passive way, trimming methods are required to correct the device inhomogeneities from manufacturing and athermal solutions are essential to oppose temperature fluctuations of the passive/active components during run-time. We present an approach to fabricate CMOS backend-compatible and athermal passive photonic filters that can be corrected for fabrication inhomogeneities by UV-trimming based on low-loss amorphous-SOI waveguides with TiO2 cladding. The trimming of highly confined 10 μm ring resonators is proven over a free spectral range retaining athermal operation. The athermal functionality of 2nd-order 5 μm add/drop microrings is demonstrated over 40°C covering a broad wavelength interval of 60 nm.
大规模集成硅光子电路存在两个不可避免的问题，这会增加整体功耗。首先，即使在亚纳米尺度上的制造缺陷也会导致光谱器件的不均匀性，这需要在器件运行期间进行微调。其次，光子器件需要进行主动校正以补偿热漂移。因此，如果不采用无热和波长可微调的解决方案，就会浪费大量功率。因此，为了以被动方式最小化光子电路的总功率需求，需要采用微调方法来校正制造过程中的器件不均匀性，并且无热解决方案对于在运行期间对抗无源/有源组件的温度波动至关重要。我们提出了一种制造与CMOS后端兼容的无热无源光子滤波器的方法，该滤波器可以通过基于具有TiO2包层的低损耗非晶硅绝缘体上硅（amorphous-SOI）波导的紫外微调来校正制造不均匀性。在保持无热运行的自由光谱范围内，证明了对高度受限的10μm环形谐振器进行微调的可行性。二阶5μm分插微环的无热功能在40°C范围内得到了验证，覆盖了60nm的宽波长区间。
