雙工次模組封裝與耦光效率之改善

Abstract

雙工次模組在結構方面，係包含了光發射次模組與接收次模組兩個部份，文中提供了一套雙工次模組封裝與測試的方式，主要利用膠封與雷射銲接的固定方式，分別地將光發射次模組與接收次模組固定於雙工次模組本體上，再依所訂立之電性規範，以篩出符合測試及可靠度條件之完成品。 本論文利用ZEMAX光學模擬軟體，找出當光耦合效率理論值為最大時，探討晶片位移量相對於符合光纖端面角度之出光角度值，實驗中選取了當光耦光效率達最大時，其該對應晶片位移量來進行實驗驗證，經過一連串的模擬嘗試與實驗驗證，我們證明當晶片以每10μm單位距離做偏移時，其TO的出光角度變化約為0.5度，依此關係來實際驗證當6°光纖斜面所對應的晶片偏移距離為60μm，其耦合效率的確為最大，比起晶片在中心位置的條件下，其耦合效率還大了5.46%，驗證了晶片偏移對於雙工次模組發射端的耦光有效性。此成果對於雷射銲接製程所產生的銲後位移，提供了一個更大的容許度。

BOSA (Bi-directional Sub-Optical Assembly) mainly includes the optical transmitter module and receiver module. This paper provides a testing and packaging method for duplex module. We treat the receiver module using epoxy gel sealing packaging method and laser welding technique for the transmitter module respectively to fix these two parts onto the metal main body. And sieve out the finished product with the laid-down electrical specifications to meet the conditions of testing and reliability.

This thesis employs optics simulation tool ZEMAX to explore the influence of active chip offset on the optical beam angle at which the beam enters the fiber end face while optical coupling efficiency reaches a maximum in theory. The experiments are conducted to observe the corresponding effect of chip offset when the coupling efficiency is fine tuned to the maximum. After a series of simulations and experiments, it can be concluded that the every 10μm chip offset gives a 0.5° TO light angle deviation. By this rule, the desired value of chip offset is calculated to be 60μm when a 6° fiber inclined plane is deployed in the BOSA structure. The coupling efficiency is also improved to the best and 5.46% higher than the conventional zero chip offset case. The effectiveness of the chip offset method is verified. The results also provide a greater tolerance for post-weld displacements generated by laser welding.