常壓電漿應用於多層玻璃之陽極接合技術開發

Development of anodic bonding technique for multi-layered glass with atmospheric pressure plasma pretreatment

詹金龍(jin-long Chan)

指導教授 ： 楊啟榮

國立臺灣師範大學/科技學院/機電科技研究所/碩士(2012年)

摘要

陽極接合技術主要是藉由電場與溫度的輔助下，形成共價鍵結而達到玻璃-矽晶圓、玻璃-玻璃基板接合之目的。由於陽極接合易於達到氣密性接合，並具有低溫、無介質、製程簡易等優勢，故已廣泛應用於微機電系統之封裝。在以往陽極接合技術中，多數研究僅只有兩層接合並應用於元件製作開發，而為了提升產品之性能及附加價值，勢必發展多層之接合技術。因此，本研究將配合常壓電漿基板表面處理技術，以進行多層玻璃(> 3 layers)陽極接合技術的研究。
根據研究結果顯示，本研究利用常壓電漿系統，使用壓縮空氣CDA作為主要製程氣體，於soda lime玻璃試片表面進行前處理，試片面積大小均為1 cm X 1 cm，唯陽極接合用之底層玻璃，其面積大小採用2 cm X 2 cm。在間距為5 mm與時間為30秒之處理條件下，使得試片表面接觸角<3 ∘，具有超親水特性(<10 ∘)，其時效性可長達八小時。藉此特性能降低接合界面之氣隙排出阻力，在間距範圍5-25 mm與時間固定為30秒之常壓電漿處理條件，以及固定接合電壓為2.5 kV、溫度200 ℃及時間1分鐘之接合條件下，氣隙排出阻力小而能有較佳之接合品質與速度，接合率均落於26.49±3 %，相較於未處理之試片僅只有7.98 %，接合率之差距至少三倍以上。
選擇常壓電漿處理時間的原則，主要依親水鍵結接枝於試片表面之穩定程度，並於後續進行陽極接合製程，其接合條件為電壓2.5 kV、溫度200 ℃及時間1分鐘。在處理時間與接合率關係圖中，得知處理時間範圍在5-30秒為線性區，其斜率值約為0.65 %/sec，處理時間範圍在30-90秒為飽和區，其斜率值約為0.08 %/sec，接合率平均在27.53 %。在處理時間90秒時，可達到30.91 %之接合率。
在100 %的面積接合實驗中，經常壓電漿處理之試片，在固定接合電壓為2.5 kV與溫度200 ℃之接合條件下，氣隙排出阻力小而較不易產生牛頓環，能完整接合得到73.3 N之剪力破壞，比起未處理之試片需克服阻力問題，可能於微觀世界中存有氣隙，使接合屬於暫時性或並非完全接合，得到43.1 N之剪力破壞，故常壓電漿對於陽極接合具有一定之重要性。
利用接合電壓2.5 kV、接合溫度200 ℃以及時間為5分鐘之接合條件，分別完成常壓電漿處理與否之三層玻璃結構的陽極接合，未經常壓電漿處理之上下層接合界面可分別得到30.3 N與56.0 N之剪力破壞，而經由常壓電漿處理可分別得到37.8 N與87.4 N之剪力破壞，表示處理對於接合力提升之必要性，接合力又因層數而有所遞減，最大之接合力主要於下層界面，亦即最大電場發生之處。
最後，依研究所提出之多層玻璃接合的方法，改善以往僅受限於三層接合或需分次接合才能達到多層結構的缺點，利用接合電壓2.5 kV、接合溫度200 ℃以及時間為10分鐘之接合條件，可於單次迅速順利進行二至七層結構之玻璃接合。

關鍵字

常壓電漿 ； 陽極接合 ； 多層結構

並列摘要

Anodic bonding technology is a method which mainly by the aid of the electric field and temperature for connecting two materials such as glass-silicon wafer or glass-glass substrate by forming covalent bonding. Anodic bonding has been widely used in micro-electro-mechanical system (MEMS) package, for its benefits of tight binding, low temperature, non-intermediate, and simple process. In the past, anodic bonding was used for bonding two layers and applied to the development of device fabrication. In order to enhance the performance and quality of products, we have to extend the bonding technology to multi-layers. Hence, we have used anodic bonding technology with the atmospheric pressure plasma pretreatment (APP), a surface treatment technology for bonding multiple layers of glass (> 3 layers) in thus research.
According to the experimental results, pretreatment in soda lime glass specimen using the APP system of clean dry air (CDA) which is the mainly used gas during process. The specimen size is about 1 cm  1 cm and the bottom glasses used in anodic bonding is 2 cm  2 cm. Under 5 mm spacing and 30 seconds pretreatment conditions, the specimen surface contact angle is less than 3 degrees with superhydrophilic property (less than 10 degrees), and the timeliness can be up to 8 hours. It can reduce the air-gap discharge resistance of bonding interface by this feature. Based on the 5-25 mm spacing and the fixed time is 30 seconds treatment conditions, and the fixed connecting voltage is 2.5 kV, temperature is 200 ℃ and 1 minute bonding conditions, the air-gap discharge resistance is small so it has batter quality and speed of connecting. The bonding ratio under the treatment of surface is about 26.49±3 %, the surface without treatment is only 7.98 %, the bonding ratio improved at least more than 3 times. In accordance with the principle of APP treatment time, the stability of specimen surface is based on hydrophilic bonding, and follow-up anodic bonding process is based on connecting voltage 2.5 kV, temperature 200 ℃ and 1 minute bonding conditions. According to diagram of treatment time and bonding ratio, the range of treatment time during 5-30 seconds is the linear region, the slope is about 0.65 %/sec, and the range of treatment time during 30-90 seconds is the saturation region, the slope is about 0.08 %/sec.
In the fully bonding experiment, samples with APP treatment under the condition of 2.5 kV and 200 ℃ can reach shear failure of 73.3 N due to low air-gap discharge resistance. On the other hand, samples without APP treatment is temporary bonded and only have 43.1 N shear failure. Hence, APP treatment has a certain importance in anodic bonding. Anodic bonding of the three layers glass structure based on connecting voltage 2.5 kV, temperature 200 ℃ and 5 minutes bonding conditions. The shear failure of top and bottom bonding level were 30.3 N and 56.0 N without the APP treatment, and the shear failure of top and bottom bonding level were 37.8 N and 87.4 N with the APP treatment. It is shown that the treatment can improve bonding performance.
Finally, the method for bonding multiple layers of glass in this examined has improved that constructing multi-layers structure should bond three layers or connect layer by layer, it is a rapid and smooth method for bonding 2 to 7 layers glass structure during one-step based on connecting voltage 2.5 kV, temperature 200 ℃, 10 minutes bonding conditions.

並列關鍵字

Atmospheric pressure plasma ； Anodic bonding ； Multi-layered structure

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