多部離子植入機台內毒氣鋼瓶的最佳化怖置

Abstract

在半導體前段製程中，離子植入製程是不可或缺的主要製程之一，每一部離子植入(Ion Implanter)機台可以安裝三種毒氣:磷化氫(PH3)、砷化氫(ASH3)、硼(BF3)。離子植入製程主要目的是藉由將雜質原子離子化後，在晶圓上我們想要植入的位置，產生我們想要之導電層(例如:N-type、P-type)，目前全球所有的離子植入(Ion Implanter)機台皆被設計為安裝三種毒氣各一瓶於氣體鋼瓶櫃(Gas box)內，實際上我們需要很頻繁的停機去更換使用完的空鋼瓶。在某工廠中, 我們根據歷史數據，估計11部離子植入(Ion Implanter)機台的三種毒氣鋼瓶之年耗量，藉由我們所建立的最佳化毒氣鋼瓶配置方法，來降低機台更換鋼瓶的當機時間和提高機台可使用率，在我們研究的個案中，大部份的離子植入(Ion Implanter)機台氣體鋼瓶櫃(Gas box)內，皆被設計為配置兩瓶相同種類的毒氣再加上一瓶另一種類的毒氣，另外我們修改每部機台鋼瓶櫃內管路的設計，來符合我們配置的毒氣鋼瓶擺放位置，我們估計重新配置的毒氣鋼瓶擺放位置可減少每月610分鐘更換鋼瓶的當機時間或增加0.9%的機台可使用率。

Within the semiconductor front-end processes, ion implantation is one of the indispensable processes. Every ion implanter can only accommodate three toxic gas cylinders: Phosphine (PH3), Arsine (AsH3) and Boron trihalides (BF3) to generate N-type and P-type dopant. All the ion implanters are designed to install each of the three toxic gas cylinders on the three positions. Ion implanter needs to shutdown to replace the empty cylinder frequently. We estimate the yearly consumption of the toxic gases on nine implanters of a factory. We develop a procedure to allocate the type of gases cylinders to the eleven implanters to reduce the total down time for replace the cylinders. In our particular case, most the implanters are installed three cylinders with two of the three types of gases, some with only one type gas. The gas box on each implanter is redesigned to adopt the new cylinder allocations. This reallocation reduced the down time: 610 minutes /month and increased the available time:0.9%.