動態焦距技術應用於半導體微影設備

Abstract

本論文探討影響半導體黃光區微影設備機台可使用時間(Available time)的原因，以降低產品修復率，提昇設備妥善率，增加晶圓廠的產量。積體電路晶圓廠半導體微影設備的維護保養與檢修是否良好可以從幾個重要指標來看，包括平均可用時間(Available time)，損壞間隔週期(MTBF，Mean Time Between Failure)，及產品修復率(Rework rate)。要降低修復率(Rework rate)，就先從分析機台Run貨之(Run product)每批報告(Batch report)的各項指標內容來進行改善，本研究經過詳細分析後，發現其中動態失焦退貨率( Dynamic focus error reject rate)是造成修復率 (Rework rate)最重要的因素。 本研究進行各項實驗並彙整各項實驗數據結果，執行分析比對，以品質管理(QC，Quality Control)七大手法當工具，找出動態失焦退貨率(Dynamic focus error reject rate)上升的原因，包括氣動避震器(Air Mount)之不穩定、凸輪 (Cam Disk) 損壞、高度量測器(Level Actuator)損壞、排線觸碰(flat cable touch)、惠普雷射發射器(HP laser head)、惠普雷射接收器(HP receiver)、動態碰觸(Dynamic shortcut )等因素，其中動態碰觸(Dynamic shortcut )是影響動態失焦退貨率( Dynamic focus error reject rate)上升的最主要原因。如何減少動態碰觸(Dynamic shortcut )產生，一般的情況下氣動避震器(Air Mount)的不穩定是造成碰觸(Shortcut)的重要因素，而形成微影曝光機台，氣動避震器(Air Mount)不穩定的原因多半是由於氣閥(Dither valve )損壞所造成的。研究中發現可以讓氣動避震器(Air Mount)回復穩定之短期立即解決方案為：(1)氣閥(dither valve )進氣量加大，(2)凸輪軸(Cam Disk)由正轉更改為反轉，(3) 排線重新整理，(4)定期清潔保養等，而長期立即解決方案為：(1)更換新的氣閥(Dither valve )，(2)更換新的凸輪軸(Cam Disk)，(3)更換新的高度量測器(Level Actuator)，(4)以及依循流程圖(Follow the OCAP )尋找解答。

This study explores the reason of Equipment Available Time for semiconductor lithography. This approach is beneficial for the reduction of product repair rate, enhancement of tool run time, and increasing the production capability. The maintenance and repair for semiconductor lithography equipment is related to several important parameters such as Average Run Time, Mean Time Between Failure (MTBF), and Product Rework Rate. After careful study, we find that the Dynamic Focus Error Reject Rate is the decisive factor for the Rework Rate. This study carried out various experiments in addition to data comparison and quality control (QC). Hence, we successfully achieve the identification of Dynamic Focus Error Reject Rate in relation to the Pneumatic Shock Air Mount Instability, Cam Disk Damage, Level Actuator Damage, Flat Cable Touch, HP Laser Head Transmitter, HP Laser Receiver, and Dynamic Shortcut.