深溝多晶遮罩開口蝕刻製程之先進製程控制

Abstract

本論文主要目的為設計一套應用於深溝多晶遮罩開口製程(Deep Trench Poly Hard Mask Open, DTPHMO)之關鍵尺寸(Critical Dimension, CD)的先進製程控制方法。首先利用相關性分析法(Correlation Analysis Method)與迴歸分析法(Regression Analysis Method)找出乾式蝕刻機台之輸入變數(製程配方，Recipes)與輸出變數(晶圓良率變數：關鍵尺寸)之間的關係；再將模型代入前饋與指數權重移動平均控制器(Feed-Forward and Exponential Weighted Moving Average, FF + EWMA)，配合前製程量測值與後量測值的變化動態調整製程輸入參數，使得後量測的關鍵尺寸可以快速且穩定地達到製程規格的目標值，以提升製程之穩定度。

This study proposes an Advanced Process Control (APC) method to control the critical dimension (CD) of Deep Trench Poly Hard Mask Open (DTPHMO) process. The correlation analysis method and regression analysis method are used to build up the prediction model between input recipes and system outputs. The measurements of pre-process and post-process are adopted to adjust the input recipes by using the feed forward and exponential weighted moving average (FF+EWMA). Results show that the critical dimension converges fast and stably to the target value. The stability of process is also increased.