《LAM4 Poly silicon rainbow Etcher》.pdf

LAM4 Poly-Silicon Rainbow Etcher 1.0 1.0 Title LAM4 Poly-Silicon Rainbow Etcher (for 4-inch wafers only) 2.0 2.0 Purpose LAM4 is a fully automated, single wafer, plasma/RIE etcher for poly-silicon film, silicon nitride film, and deep bulk silicon etching on 4-inch wafers. It can also etch germanium and germanium/silicon mixed films. 3.0 3.0 Scope This document provides the following information: ► ► General operation procedures of LAM4. ► ► Recipe loading, editing, and saving to the floppy/hard drive. ► ► User level trouble shooting. ► ► Setup and monitor etch endpoint trace. 4.0 4.0 Applicable Documents 4.1 4.1 Rainbow 4420 Operations and Maintenance Manual, Lam Research Inc. (copy in Office). 4.2 4.2 Microlab Online Manual Chapter 7.0 (LAM Etcher Overview). 4.3 4.3 Material Safety Data Sheets for O , Cl , HBr, Ar, He, SF , and CHF (copy in 2 2 6 3 Lobby). 5.0 Definitions Process Terminology 5.1 5.1 Plasma/RIE Etcher: This kind of etcher uses gas radicals formed in the plasma generated by RF power to etch film on the wafer. The wafer is placed on the grounded electrode, for the plasma etcher, to reduce radiation damage on the devices. For RIE etcher the wafer is placed on the powered electrode that induces ion bombardments on the wafer to increase etch rate and anisotropy. 5.2 5.2 Etch Rate: The thickness of the film etched per unit time, usually in Å/minute. 5.3 5.3 Etch Uniformity: It is defined as (maximum etch rate – minimum etch rate)/(maximum etch rate + minimum etch rate), usually in %. 5.4 5.4 Etch Selectivity: The etch rate ratio between two different films/subst