考慮等候時間限制之擴散區生產派工法則

Abstract

本研究探討晶圓製造的擴散區之派工問題。擴散區之生產情境如下：(1)已知機台組合及產品需求組合；(2)生產系統是三階段的流程式生產線，第一及第二階段，各機台的加工單位為單批加工，第三階段為批次加工，相同產品才可並批；(3)產品在第二、三階段有等候時間限制，產品之等候時間超過上限時，皆須重回第一階段重新加工。本研究提出第三階段工件Rework-DJAH派工法則，考量整備時間、等候時間與重工時間，以邊際成本最小值為目標，求解爐管區產品加工的時間點與批量。 本研究在給定的機台組態、投料速度與產品組合，考慮爐管區生產績效，包含總產出、在製品平均數、生產週期、回流數量與機台使用率，建立EM-Plant8.1模擬流程，驗證Rework-DJAH派工法則與文獻的DJAH派工法則之績效。最後透過統計檢定分析模擬蒐集的數據，結果顯示，Rework-DJAH有效降低回流數量，且其他績效與DJAH無顯著差異。

In this study we propose a Rework-DJAH dispatching rule for the diffusion stage in semiconductor manufacturing. The production system in the diffusion stage is as following：(1) There are three series operations: B-cleaner, STD-cleaner and Gate_OX. The processing lot in B-cleaner and STD-cleaner is single lot, and in Gate_OX it is batch-lot. The configuration of machine is given, i.e., M1, M2 and M3 parallel machines for the three operations respectively. (2) There are job waiting constraints before STD-cleaner and Gate_OX machines respectively. Reworks from B-cleaner are required for those jobs’ waiting time violated one of the constraints. Rework-DJAH dispatching rule is proposed for Gate_OX. Considered the set-up time, waiting time and reworking time for each product type in the queue, we determine the loading product type and its batch size. Then we build a simulation model by the EM-Plant 8.1 to evaluate the performances of Rework-DJAH dispatching rule. We find Rework-DJAH dispatching rule is better then DJAH dispatching rule in the numbers of rework job. However they are no significant difference in the numbers of throughput and work in process, the working percentage of Gate_OX and the cycle time.