LPCVD製程設備中晶圓與反射板之熱輻射分析

Analysis of Radiation in LPCVD Furnace - Guard Rings and Holders

王中明(Chung-Ming Wang)

指導教授 ： 林育才

元智大學/工程學院/機械工程學系/碩士(1998年)

摘要

低壓化學氣相沈積LPCVD為IC晶片製造的重要製程之一。與傳統加熱爐比較之下，由於高速加熱(RTP)反應爐有體積小、快速加熱、低耗能等降低成本的優勢，因此需要低壓且快速加熱的LPCVD製程會採用RTP反應爐為其加熱設備，不過在快速加熱的過程中晶圓表面溫度分佈的不均勻，常造成化學反應不均勻(如沈積、氧化等)與過強的熱應力，嚴重影響晶圓的品質。本研究將針對RTP反應爐體內反射板或托盤等設備元件進行研究，探討不同形式的元件與不同的幾何位置，對晶圓表面溫度分佈均勻性的影響，作為改良LPCVD反應爐設計之依據，提升製程的品質。
結果顯示，不同元件會對晶圓表面造成截然不同的溫度分佈。其中圓形外環反射板與圓形托盤在某些參數的配合下，能有效的改善晶圓表面溫度分佈不均勻，增加每片晶圓可利用面積。

關鍵字

低壓化學氣相沈積 ； 高速加熱爐 ； 反射板 ； 托盤 ； 熱輻射

並列摘要

Low pressure chemical vapor deposition (LPCVD) process is one of the most important manufacturing processes to make electrical circuits. Compared to traditional heating furnaces, the manufacturing cost of rapid thermal process (RTP) furnaces is relatively low due to the following advantages : smaller size, shorter heating time, and low energy consumption. Therefore, LPCVD processing equipment can use RTP furnace to build a low pressure and rapid heating environment. However, the nonuniformity of temperature distribution across the wafer during the rapid thermal process is still a problem. The nonuniformity would result in nonuniform deposition layer on the wafer. Furthermore, it would cause strong thermal stresses on the wafer and reduce the yield of the product. The purpose of the study focuses on the analysis of different types of reflector or holder in a RTP furnace. The radiative phenomena during the LPCVD process is analyzed and the effects of the parameters, such as the type of the reflectors or holders, geometrical arrangement of reflectors and the wafer, etc., on the wafer temperature uniformity are numerically investigated.
The results show that the type of different reflectors or holders has pronounced effect on the temperature distribution of wafer. Circular ring reflector and holder with appropriately adjusted parameters can dramatically reduce the nonuniformity of temperature distribution across the wafer.

並列關鍵字

LPCVD ； RTP furnace ； guard ring ； shield ring ； holder ； radiation

參考文獻

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