Application of backside fiber-optic system for in-situ CMP endpoint detection on shallow trench isolation wafers

被引：4

作者：

Bakin, DV ^{[1
]}

Glen, DE ^{[1
]}

Sun, MH ^{[1
]}

机构：

[1] Luxtron Corp, Santa Clara, CA 95051 USA

来源：

PROCESS, EQUIPMENT, AND MATERIALS CONTROL IN INTEGRATED CIRCUIT MANUFACTURING IV | 1998年 / 3507卷

关键词：

chemical-mechanical planarization; endpoint detection; shallow trench isolation process; interferometry; fiber-optic sensor; wafer manufacturing control;

D O I：

10.1117/12.324343

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

A method of Chemical-Mechanical Planarization (CMP) Endpoint Detection (EPD) of Shallow Trench Isolation (STI) wafer is discussed in this paper. The detection algorithm was developed based on the interferometric intensity modulation of the light reflected from the wafer being polished The physical model of the process proved to reliably predict behavior of the reflected signal during successive removal of a silicon oxide film and transition into patterned silicon nitride layer. The model calculates film thickness removed from STI wafers with known layer structure, from the reflected signal recorded during CMP process. The in-situ miniature system incorporating fiber-optic coupled diode laser and InGaAs photodetector was successfully implemented for the purpose of Endpoint Detection. On a patterned wafer the system can control nitride thickness removal with a better then 200 A accuracy. The wireless modular design permits real-time simultaneous multiple points operation in a fully automated mode.

引用

页码：201 / 207

页数：7