添加鐵及氧化釔對反應燒結氮化矽之氮化行為影響與銅接合行為之研究

Abstract

由於反應燒結氮化矽製程擁有較低經濟成本、較好的尺寸控制以及較低的反應燒結溫度，因此燒結氮化矽製程受到廣泛地關注及研究。在本研究中，將對添加鐵以及氧化釔兩種不同的矽粉，在1400°C完成氮化反應後，進行微結構的觀察及其熱傳導性質的測量，以觀察不同添加劑對反應燒結氮化矽的影響。在添加鐵的系統中，促進氮化率及相對密度，使得在較短的燒結時間內，得到最高的數值。另外，添加鐵也促成α→β氮化矽相變行為，而在系統中誘導形成柱棒狀β 相的氮化矽生成。當系統中添加氧化釔時，因著氧化釔易與矽粉表面的二氧化矽反應，透過在系統中反應生成Y2Si2O7 相，大量地降低了系統中二氧化矽的量。此外，在本研究中，也研究不同的溫度曲線對反應燒結氮化矽之氮化行為的影響。 在本研究中，引用共晶接合之技術，以進行反應燒結氮化矽與銅片的直接接合。共晶接合技術是利用銅與氧的共晶溫度，在銅表面形成銅-氧混合物的液相，來濕潤陶瓷表面，進行降溫以後，得到銅片與陶瓷良好接合。在進行此接合技術前，首先需要對反應燒結氮化矽進行在1300°C氧化以及在不同溫度下對銅片進行氧化。在氧化程度較高的銅片中，成功地與氮化矽完成接合。另外，在氮化矽表面，因氧化行為所生成的二氧化矽層之形貌，影響銅-氧混合物液相在氮化矽表面的的濕潤性，並決定接合的程度。

Because of economic feasibility, dimensions control and low processing temperature, the reaction-bonded silicon nitride (RBSN) process has received extensive attention. The microstructure and thermal conductivity of the reaction-bonded silicon nitride (RBSN) specimens, containing 2wt% Fe and 2wt% Y2O3, were investigated in the present study. The addition of iron promotes the extent of nitridation and the relative density of the RBSN. The addition of Fe also affects the α→β Si3N4 transformation and induces the formation of rod-like β-Si3N4. The addition of Y2O3 reduces the amount of silicon oxide through the reaction of SiO2 to form Y2Si2O7 phase. In the present study, the effects of stepwise heating profile on the nitridation are also investigated. In the present study, a eutectic bonding technique is used to join copper plate to reaction-bonded silicon nitride. The RBSN specimens were oxidized first at 1300°C. The copper plate was also oxidized at various temperatures. The microstructure and thermal conductivity of RBSN/Cu laminate were investigated in the present study. The bonding was achieved as the extent of oxidation is high. The morphology of SiO2 layer affected the wetting between RBSN and Cu. To the resolution of the scanning electron microscope, no Si-Cu-O compound is found at the interface between oxidized RBSN and copper. The infiltration of Cu-O melt into the SiO2 layer helps the bonding between RBSN and Cu.