| 摘要: | 本論文提出一個將高分子聚合物波導和具45?反射面矽基光學平台整合之垂直耦光光路，並成功整合雷射光源、光偵測器、驅動電路與放大電路於單晶片模組，其為光學連接技術領域首次達成在單晶片上的單通道20-Gbps光學連接模組。本模組架構建立在一個具有45?矽基反射面之高分子聚合物波導之矽基光學平台上，利用驅動電路與放大電路對面射型雷射及光偵測器進行控制。其雷射光源經由45?反射面達到非共平面轉折，並耦合至高分子聚合物波導；再藉由相對應之45?反射面，將波導內的光訊號耦合至光偵測器。採用具45?反射面之矽基光學平台，可達到三維光路之建構，並連接模組之發射端與接收端。
本光學連接模組具有高光學耦合效率且製程簡單，波導核心製程可自由調整變化其比例，以達到主動光電元件與光波導之結構尺寸匹配。高精度之覆晶封裝技術可將面射型雷射與光偵測器封裝於矽基光學平台上，其對位精度可控制在±5 m。經由覆晶封裝技術與45?矽基反射面之高分子聚合物波導之發展，面射型雷射至光偵測器之光學耦合效率可達到34 %。
在高頻訊號量測方面，本模組架構可達到單通道20-Gbps高速傳輸能力。其模組輸入訊號為27-1的假隨機二進位序列(Pseudo Random Binary Sequence, PRBS)。模組發射端之雷射驅動電流與調製電流分別為8.3 mA與±4.69 mA，；模組接收端之光偵測器操作逆向偏壓為1.7 V。本模組發射端至接收端之眼圖量測，其抖動(jitter)為17.681 ps、眼高(Eye Height)為123 mV，訊號之訊雜比可達到7.56。量測之誤碼率可低於10-12等級，證明了本模組具有20-Gbps高頻傳輸能力。
In this investigation, an on-chip 20-Gbps optical interconnect module is realized on polymer waveguides terminated with 45° micro-reflectors as vertical couplers. The proposed module including vertical-cavity surface-emitting laser (VCSEL), Photodetector (PD), driver IC, and amplifier IC is constructed on single silicon substrate. It’s first time to demonstrate a 20-Gbps per channel in on-chip optical interconnect.
The driver and amplifier IC are employed to control the VCSEL and PD, respectively. In the transmitting part, the lightwave emitting from VCSEL impinge upon 45° micro-reflectors, and couple into polymer waveguide. In the receiving part, the lightwave propagating in the polymer waveguide is bent by 45° micro-reflectors and emitted into PD. Due to adopt the polymer waveguides terminated with 45° micro-reflectors, the lightwave could be formed three-dimensional optical, and connect the optical signal between transmitting and receiving parts.
The proposed optical interconnect provide the benefit of high optical coupling efficiency and simply fabrication process. Due to tune the geometric core size of polymer waveguide, the optical mode between active photoelectric components and polymer waveguide could be matched to enhance the optical coupling efficiency. The high precision flip-chip technique could be employed to assemble the VCSEL and PD on proposed module, the assembling alignment tolerance could be controlled within ±5 um. The optical coupling efficiency between VCSEL and PD is measured as 34%
In the high–speed signal measurement, the 20-Gbps error-free transmission with pseudo-random binary sequence (PRBS) of 27-1 is demonstrated. In this module, the driving and modulation current is set as 8.3 and ±4.69 mA, respectively, and the reverse bias of PD is about 1.7 V. In the eye diagram measurement, the jitter of 17.681 ps and eye height of 13 mV are measured. The signal-to-noise ratio is measured as 7.56. The bit error rate could be pass the 10-12, it’s prove that the proposed module can be used in transmission of data-rate of 20-Gbps. |
