SnO-MgO-P2O5熔接玻璃的結晶, 熱性質及耐水性之研究

Crystallization, Thermal Properties, and Water Durability of SnO-MgO-P2O5 Solder Glass

葉志賢(Chih-hsien Yeh)

指導教授 ： 徐錦志

大同大學/工程學院/材料工程學系所/博士(2011年)

摘要

熔封玻璃材料已被使用在顯示器、微電子、半導體等領域，以接合玻璃-玻璃、玻璃-金屬、玻璃-陶瓷及金屬-陶瓷等元件。熔封玻璃材料的特性要求主要是低軟化溫度，熱膨脹係數儘量接近待接合元件，良好的化學耐蝕性。磷酸鹽玻璃通常有低軟化溫度，使其成為取代含鉛低溫接合玻璃的重要材料。磷酸鹽玻璃之最大缺點是化學耐蝕性不佳及熱膨脹係數不易降低。本研究之目的為探討SnO-MgO-P2O5熔接玻璃的結晶、熱性質及耐水性。以下為研究的結果：

(1) 低黏度SnO-MgO-P2O5 玻璃的燒結與結晶性質
本研究係以無鉛低黏度60SnO-10MgO-30P2O5 (mole%)玻璃粉末為實驗材料。研究其燒結性、結晶傾向與燒結後的玻璃性質。實驗結果發現，玻璃粉末生胚於362C即可達燒結緻密化，並在417C可於基板上呈現良好攤覆性。而燒結體的性質 (熱膨脹係數與耐水性)受燒結溫度及燒結時所產生的結晶相影響。

(2) 燒結氣氛對SnO-MgO-P2O5玻璃粉末的微觀結構及耐水性之影響
本研究主要目的在探討燒結氣氛 (Ar、air及O2)對60SnO-10MgO-30P2O5 (mole%)玻璃粉末的燒結性、結晶性及燒結後耐水性的影響。由實驗結果發現，當氧分壓增加，促進玻璃顆粒表面的Sn2+氧化成Sn4+的程度愈明顯，使玻璃的表面黏度上升，導致燒結溫度提高及結晶相生成溫度移往高溫。燒結氣氛影響燒結體的表面孔洞率及結晶相的種類及含量，進而影響耐水性。

(3) 熱處理氣氛對SnO-P2O5玻璃塊材的微觀結構及耐水性之影響
本研究主要目的在探討燒結氣氛 (Ar、air及O2)對60SnO-40P2O5 (mole%)玻璃粉末的燒結性、結晶性及燒結後耐水性的影響。由先前實驗結果，當氧分壓 (PO2)增加，促進玻璃顆粒表面的Sn2+氧化成Sn4+的程度愈明顯。而實驗中進一步發現發現，玻璃的表面狀態，如硬度及結晶相的生成也受熱處理氣氛影響，進而影響玻璃的耐水性。隨氧分壓增加，重量損失降低 (於浸漬120 min後，分別從Ar的5.42降至O2的3.2210-4 g/cm2)。於O2氣氛下熱處理後的玻璃有好的耐水性。

(4) 添加低熱膨脹係數陶瓷粉末對SnO-MgO-P2O5玻璃的燒結性、結晶行為與燒結後性質之影響 (乾壓成型方式)
本研究主要目的在探討同時添加兩種不同低熱膨脹係數之陶瓷粉末於60SnO-10MgO-30P2O5 (mole%)玻璃粉末中，希望可降低陶瓷顆粒-玻璃基地界面之局部熱應力，並與低熱膨脹性元件接合。ZrSiO4及β-spodumene有溶入SnO-MgO-P2O5玻璃之現象，當陶瓷填充劑熔入玻璃中會改變玻璃成分，進而影響複合材料於燒結後的性質。孔洞率基本上隨添加的總陶瓷填充劑增加而增加。與SMP玻璃相較下，添加ZrSiO4較易使Sn3(PO4)2相生成，而添加β-spodumene則可抑制Sn3(PO4)2相生成。添加ZrSiO4及β-spodumene後的熱膨脹係數，由純SMP玻璃的120×10-7/C降至83×10-7/C。

(5) 複合材料與Al2O3陶瓷基板之接合 (厚膜塗佈方式)
純60SnO-10MgO-30P2O5 (mole%)玻璃與Al2O3基板界面間並無黏著，係因玻璃與Al2O3熱膨脹係數差異太大，並於降溫時產生明顯裂縫。所有複合材料與Al2O3基板之界面間均無明顯裂縫存在，且於Al2O3基板上黏著性良好。複合材料要與Al2O3基板以低溫 (407C)長時間 (60 min-120 min)或以高溫 (434C-470C)短時間 (10 min)始有熔接效果。

關鍵字

結晶性 ； 熔接玻璃 ； 耐水性

並列摘要

Solder glasses have been used in the areas of displays, microelectronics, and semiconductor technologies to fabricate glass-to-glass, glass-to-metal, glass-to-ceramic, and metal-to-ceramic joints. The major property-requirements for soldering are low softening temperature, thermal expansion coefficients match to the devices to be soldered, and acceptable chemical durability. Phosphate glasses, due to their low viscosities, are possible alternatives to PbO-based glasses. The major shortcomings of phosphate glasses are poor chemical durability and too high thermal expansion coefficient. In this research is to study the crystallization, thermal properties, and water durability of SnO-MgO-P2O5 solder glass. The results are as follows:

(1) Sintering, Crystallization, and Properties of SnO-MgO-P2O5 Glass
In this study, the SnO-MgO-P2O5 solder glass powder was fabricated. Sinterability, wetting, flowability, crystallization, and the resulting properties of the glass powder were investigated. It is shown that the powder compact can be fully densified above 362C and show good wetted to the substrate above 417C. The properties (coefficient of thermal expansion and chemical durability) of the sintered glass depend on the sintering temperature and are discussed in terms of the development of crystalline phases during sintering.

(2) Influence of Sintering Atmosphere on the Microstructure and Water Durability of
SnO-MgO-P2O5 Glass
In this study, effects of sintering atmosphere (Ar, air, and O2) on the sinterability and crystallization at 380C-470C of 60SnO, 10MgO, 30P2O5 (mole%) glass powder, and the water durability of the sintered glass were investigated. Increasing the oxygen partial pressure (PO2) in the sintering atmosphere enhanced the oxidation tendency of Sn2+ to Sn4+ near the surface region of the glass particles. Therefore, the glass viscosity was increased, resulting in the increase in both the temperature of densification and the temperature at which crystalline phases developed. Phase assemblage and the amounts of crystalline phases were also affected by PO2. The water durability of the sintered glasses is discussed in terms of the above microstructural parameters.

(3) Influence of Heating Atmosphere on the Properties of Stannous Phosphate Glass
In this study, a the 60 SnO - 40 P2O5 (mole%) glass was reheated at 280C (about 45C above the glass-transition temperature) for 20 min in various atmospheres (Ar, air, and O2), then the structure and surface-related properties were examined. It was found that increase in PO2 increases surface hardness, reduces optical transmittance, and improves chemical durability. The above phenomena are explained in terms of the increased oxidation tendency of Sn2+ to Sn4+ on the glass surface during reheating in increased PO2.

(4) Sintering, Crystallization, and Properties of SnO-MgO-P2O5 Solder Glass filled
with Low coefficients of thermal expansion filler. (Dry pressing method)
In this study, the ZrSiO4 (denoted as Z) and β-spodumene (denoted as S) ceramic powder were added into the 60SnO-10MgO-30P2O5 (mole%) glass powder (denoted as SMP) to reduce the thermal expansion coefficient of the sealing material. Effects of the addition of Z/S filler and the S particle size on the formation and properties of the Z/S-filled SMP composites were investigated. The Z/S particles would partially dissolve into the viscous SMP glass during sintering. The SMP glass with modified compositions also due to Z/S particles dissolution might have slow crystallization kinetic (composition effect). The internal porosity increased with increasing the amount of ceramic powder. Compare with the SMP glass, the current study shows that added ZrSiO4 powder improved the development of the S3P phase and β-spodumen powder inhibited the development of the S3P phase. The thermal expansion coefficient of the sintered bodies can be effectively reduced from 120  10-7/°C for pure SMP to 83  10-7/°C for Z/S-filled compositions.

(5) The SMP-Z-S composite for soldering Al2O3 substrate (Thick-film coating method)
In this study, the composite (SMP-Z-S) was used to join Al2O3 aubstrate. During the joining, although 60SnO-10MgO-30P2O5 (mole%) solder glasses can provide adequate flow at the soldering temperature, their thermal expansion coefficient are too high to match Al2O3 substrate. All of the SMP-Z-S composites showed good sealant for Al2O3 substrate.The composites can be soldering with Al2O3 substrete when the composites/Al2O3 is heated at lower temperatures (e.g., 407C) for 60 min-120 min, or at higher temperatures (e.g., 434C-470C) for 10 min.

並列關鍵字

water durability ； crystallization ； solder glass

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