半導體晶圓製造廠中等候時間限制作業的放行控制方法

Release Control Methods for Queue Time Limit Operations in Semiconductor Wafer Fabrication

巫啟彰(Chi-Jang Wu)

指導教授 ： 洪一峯

國立清華大學/工學院/工業工程與工程管理學系/碩士(2006年)

摘要

在半導體製造業中，有關等候時間限制 ( Queue Time Limit )的研究不多，本論文研究方向在於有等候時間限制的放行控制法則 – 模擬控制法則 ( Simulation-based Control Rule )、等候線估計控制法則 ( Queue Estimate Control Rule )，兩種控制法則針對在不同的等候時間限制、不同的產能水準下，是否能夠減少批量重工次數、提高產出率。完全放行法則 ( All Release Rule )，則是用來做為在等候時間限制下，沒有使用控制法則的情形，做為有使用控制法則的對照比較。
模擬控制法則是由涂 【2005】 提出，對於有等候時間限制的批量放行與否，用模擬的方式評估，即建立一模擬環境與實際環境完全相同，對於被評估之批量能在模擬環境中的不超過等候時間限制，才允許此批量在實際環境中放行以進行加工。
等候線估計控制法則，是由Leachman 【1988】 所提出的等候線管理 ( Queue Management, 簡稱QM ) 的觀念而得。Leachman的等候線管理是以工作站觀點來計算等候線長度隨時間變化的情況，而本論文所提出的等候線估計控制法則，則是以批量的觀點，計算批量在途程上的各工作站，在批量抵達的時間點，計算其工作站等候線長度的估計，藉此來判斷此批量在此等候時間限制的條件下，是否該進行加工。
本論文研究目的在於利用等候時間限制下的放行控制法則 ( 簡稱為控制法則 ) ，使批量尚未投入加工時，即可預測批量是否能在等候時間限制之內被加工，藉此降低批量重工次數以及提高單位時間的產出。經實驗分析，完全放行法則在各種等候時間限制之下，當投料量漸增時，批量重工次數也隨之增加。模擬控制法則在各種等候時間限制之下，在高投料量時，批量依然可以維持在低重工次數。等候線估計控制法則，在等候時間限制較短的情況，其表現略優於完全放行法則，在等候時間限制較長的情況，其表現則接近模擬控制法則。

關鍵字

等候時間限制 ； 模擬 ； 等候線管理 ； 放行控制

並列摘要

This thesis investigates the release control rule for the operation with queue-time-limit in semiconductor wafer fabrication. There are only a few researches on this subject before. This study compares two release control methods – simulation-based control rule, queue estimate control rule. The objective is to reduce the number of rework and increase throughput rate. This study experiment the above two rules under different level of the queue time limit and production rate. This thesis uses a third method – all release rule – to represent the situation without control rule and compares the above two control rules.
The simulation-based control rule proposed by Tu 【2005】 builds a simulation environment similar to real environment and determines whether a lot will be processed within the queue time limit if the lot is released at dispatch time.
The queue estimate control rule proposed in this thesis is based on the Queue Management proposed by Leachman 【1988】. This method is to estimate the queue length of the workstations on the route of the evaluated job. Comparing the queue length and the queue time limit will decide if the evaluated jobs should be released or not.
The experiment of study research shows that the rework times of the job can be greatly reduced and the throughput can be largely increased by using proper releasing control . The simulation-based control rule outperforms the other rules under various conditions. The queue estimate control rule under low machine loading is not better than the third method – all release rule. In high machine loading, the queue estimate control rule is as good as the simulation-based control rule.

並列關鍵字

Queue Time Limit ； Simulation ； Queue Management ； Release Control

參考文獻

Scholl, W. and Domaschke, J. (2000), “Implementation of modeling and simulation in semiconductor wafer fabrication with time constraints between wet etch and furnace operations”, IEEE Transactions on Semiconductor Manufacturing, Vol. 13. No. 3, pp. 273–277.

Robinson, J.K. and Giglio, R. (1999), Capacity Planning for Semiconductor Wafer Fabrication with Time Constraints Between Operations, Simulation Conference Proceedings, 1999. Winter, Phoenix, A.Z., USA, Vol. 1, pp. 880-887.

Jongsoo Kim, Robert C., Leachman, and Byungkyoo Suh (1996), “Dynamic Release Control Policy for the Semiconductor Wafer Fabrication Lines”, The journal of the Operational Research Society, Vol. 47, No. 12 (Dec., 1996), 1516-1525.

Leachman, R.C., Solorzano, M., and Glassey, C.R. (1988), A Queue Management Policy for the Release of Factory Work Orders, Eng. Systems Research Center, University of California, Berkeley. rep. no. 88-19.

蔡啟聰 (1996)，晶圓製造廠考慮等候時間限制之派工策略，交通大學工業工程研究所碩士論文。