變壓器耦合電漿蝕刻系統開發與製程參數之探討

Development and Process Parameters of Transformer Coupled Plasma Etching System

徐瓊芳(Chiung Fang Hsu)

指導教授 ： 莊賦祥

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2010年)

摘要

高科技之半導體製程、光電、太陽能及微機電產業中以電漿技術大量廣泛應用，目前產業界最常用為電感耦合電漿蝕刻設備，主要能比傳統型電漿產生更高的電漿密度。隨著積體電路尺寸奈米化、製程良率及製程片數的需求，要求製程設備的條件也不斷提高，未來變壓器耦合電漿(Transformer Couple Plasma ,TCP)是最具商業化潛力的高密度電漿蝕刻系統設備。本論文以變壓器耦合電漿蝕刻設備（TCP）為主，將改變不同的電極線圈、氣體成份比例、反應腔體壓力、上電極線圏功率大小及下電極偏壓等製程參數，探討不同製程條件對晶片的蝕刻率及均勻性的影響。最後基座設定不同的冷卻溫度及基座通入氦氣並調整不同壓力之參數，探討製程蝕刻時在晶片所產生之溫度影響。
研究結果中以上電極線圈為5圈時蝕刻速率及不均勻性最佳，蝕刻速率及不均勻性分別達到950 Å/min及3 %。當基座通入氦氣壓力在9 torr及冰水機維持溫度為0℃時，蝕刻製程中使基座溫度維持在60 ℃以下。當Cl2與BCl3製程氣體總流量50 sccm、BCl/(Cl2+BCl3)氣體混合比例為80 %、上電極線圏功率為750 W、下電極偏壓功率為300 W及反應腔壓力在4 mtorr時，有最佳蝕刻速率為1000 Å/min以上及非均勻性達到3%以下。

關鍵字

關鍵字:變壓器耦合電漿 ； TCP ； 蝕刻 ； 藍寶石基板

並列摘要

Plasma technology has been widely used in high-tech semiconductor manufacturing, photovoltaic, solar industry and micro electro-mechanical manufacturing. In industry, the most commonly used is inductively coupled plasma (ICP) etching equipment, which can generate higher plasma density than the traditional plasma source.
With the technique progress in semiconductor industry, such as integrated circuit dimension nano down, mass production speed and yield being increased, the process equipment requirements are also constantly urgent. The transformer-coupled plasma (TCP) is highest potential for commercialization of high density plasma etching system.
In this thesis the transformer coupled plasma (TCP) etching equipment was designed by studying the etching rate and uniformity on sapphire substrate with respect to the different electrode types, gas compositions, reaction chamber pressures, powers of upper electrode coil, and botanical electrode bias, etc. During the etching processes, the wafer temperature on the substrate holder was studied according to experimental parameters, such as helium gas flow rate and chiller water temperature inside the substrate holder and the etching pressure during the etching process.
The results show that 5 ring coil of upper electrode coil can be the best coil structure which results in a etching rate and non-uniformity of 950 Å/min and 3%, respectively. When the Helium pressure for substrate cooling was kept at 9 torr and chiller water temperature at 0°C, the substrate holder can be maintained below 60 °C during the etching process. The etching parameters were set as following: the total gas flow rate for Cl2 and BCl3 as 50sccm, BCl3/(Cl2 + BCl3) ratio as 80%, the upper electrode coil power at 750W, bottom electrode bias power at 300W, reaction chamber pressure in 4 mtorr. The experimental results show the etching rate more than 1000 Å/min and the non-uniformity reached 3%.

並列關鍵字

Keywords: transformer coupled plasma ； TCP ； etching ； sapphire

參考文獻

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