Abstract: A vertical rapid thermal processing (RTP) system (10) is provided, comprising a vertical process chamber (20) extending along a longitudinal axis (X), and a movable platform (32) disposed within the process chamber and having a support surface upon which one or more substrates such as semiconductor wafers (W) may be mounted for processing. A temperature control subsystem (56, 58, 60) establishes a continuous temperature gradient within the vertical process chamber along the longitudinal axis. The temperature control subsystem comprises a plurality of chamber sidewall heating elements (24) located at different vertical positions along the longitudinal axis. Each of the plurality of heating elements is controlled independently of the other of the plurality of heating elements.

Abstract: A method for determining the end point for a physical etching process step measures the current at the target being etched and detects changes in the current. Changes in the current measured at the target are indicative of transitions between dissimilar materials or of depth of penetration in a particular material. Momentary changes in the etching flux of the physical etching process are factored out by measuring the current on a mask placed in the vicinity of the target and by subtracting mask current from current measured at the target.