流量平衡為導向的黃光區綁機派工法

Abstract

隨著半導體晶圓製造的進步，產品規格精密度要求與日俱增，在晶圓的關鍵製程--黃光微影作業中，由於誤差可容忍度愈來愈小，必須藉由通過固定加工機台的方式，以提昇產品的良率，形成綁機(machine-dedication)限制的問題，當批量做出綁機決策後，及成為該綁機生產線的負荷。 派工法則為製造現場動態控制產品生產週期時間的方法。過去討論綁機情境下的派工法則相當少見。本研究提出考慮綁機負荷與機台可用產能的批量綁機決策，以及流量平衡觀念的黃光區派工法則，透過模擬實驗發現，黃光派工方法對於平均生產週期時間與達交率的績效，相較過去的方法，確有顯著改善，而本研究所提出之批量綁機決策，則無優於過去的方法。

The improvement of semiconductor manufacturing technology yields a machine-dedication characteristic. In a wafer fab, a wafer has to visit a workstation several times. A workstation involves a group of machines that are functionally identical. Yet, for some critical workstations, the processing of wafers is in high resolution and should be machine-dedicated. That is, a wafer visiting a machine one time has to be dedicated on the machine for the rest of operations. Dispatching rules concerning the machine-dedication feature has been rarely investigated in literature. This research proposed a SA (starvation avoidance) rule for allocating the wafer lots to the dedicated machines and a flow-balance rule for dispatching the dedicated machines. Extensive simulation experiments show that the flow-balance dispatching rule outperforms the previous methods. Yet, there is no significant difference between the SA allocation rule and others.