錫銲構裝光纖套管及次載具與基板經溫度循之研究

Abstract

本論文探討半導體雷射模組構裝經溫度熱循環後產生位移之研究，論文共分兩部份，第一部份為錫銲固定光纖套管位移之研究，半導體雷射光源耦合到光纖的對準固定結合中，經常以錫銲將光纖固定於金屬套管中，然後再做雷射銲接固定之結合，但光纖在金屬套管製程中並非處於中心點，而是有偏位移的情況存在，由於偏位移會對金屬套管內的光纖產生不同的殘留應力，因此金屬套管在做溫度熱循環實驗時，會因為應力不同而使得光纖產生位移。實驗結果發現光纖位移量隨溫度熱循環次數增加而遞增，然後穩定，同時光纖位移的增加而有正比的間係。在光纖偏位移為103um時，經過500次溫度熱循環後，光纖會產生0.77um的位移。 第二部份為介金屬化合物（IMC）成長之研究，半導體雷射構裝中最常使用錫銲構裝，而高溫錫銲材料與光電材料接觸後，其接合面會形成新的化合物，通常稱為介金屬化合物。實驗結果發現IMC的厚度會隨熱循環次數的增加而成長然後飽和。以PbSn 為錫銲材料，其IMC由5.36um成長至 13.86um 及以AuSn為錫銲材料，其IMC 由2.84um成長至 8.96um。並由次載具與基板推力實驗及其錫銲材料與破裂面發現，IMC成長厚度與錫銲材料機械強度有對應性。錫銲材料機械性質的改變，係由於錫銲材料經溫度循環後可能有裂縫產生，因此破裂面有脆性發生。

In this study ,we presented the measurement of the fiber shift and the intermetallic compound (IMC) growth under temperature cycling test. The thermally induced fiber shifts under a temperature cycling test of an optical fiber soldered into a ferrule packaging was measured experimentally. Up to a 0.77um of the fiber shift was found after 500 temperature cycles. Results showed that the fiber shift increased as the fiber eccentric offest increased. This fiber displacement may arise from the residual stresses within the solder during the temperature cycling tests. The growth thickness of the intermetallic compound (IMC) within the solder was also measured experimentally. Results showed that the thickness of IMC increased and then became stable after temperature cycling tests, The IMC growth thickness for PbSn and AuSn solders were 5.4 to 13.9 and 2.8 to 9 um ,respectively. The shear stress test of submount and substrate joint with solders showed that there was a correlation between joint strength and IMC thickness. The joint strength decreased between submount and substrate after temperature cycling may be the crack defect within the solder.