System and method of arc detection using dynamic threshold

Abstract

The present invention is directed to circuits, systems, and methods to quickly to quench an arc that may form between high voltage electrodes associated with an ion source to shorten the duration of the arc and mitigate non-uniform ion implantations. In one example, an arc detection circuit for detecting an arc in an ion implantation system includes an analog-to-digital converter (ADC) and an analysis circuit. The ADC is configured to convert a sensing current indicative of a current being supplied to an electrode in the ion implantation system to a digital current signal that quantifies the sensing current. The analysis circuit is configured to analyze the digital current signal to determine if the digital current signal meets threshold parameter value and in response to the digital current signal meeting the threshold parameter value, provide an arc detection signal to a trigger control circuit that activates an arc quenching mechanism.

Description

[0001] References to related applications [0002] This application claims priority to U.S. Application Serial No. 16 / 225,298, filed December 19, 2018, entitled "A SYSTEM AND METHOD OF ARCDETECTION USING DYNAMIC THRESHOLD," which reads Incorporated herein in its entirety by reference. technical field [0003] The present invention relates generally to ion implantation systems, and more particularly, to an arc detection circuit and method for detecting arcs that may form within an ion implantation system. Background technique [0004] Ion implantation systems are used to apply impurities (called dopant elements) into a semiconductor substrate or wafer (often called a workpiece). In such systems, an ion source ionizes the desired dopant element, and the ionized impurities are extracted from the ion source as an ion beam. Ion beams are directed (eg, swept) across respective workpieces to implant ionized dopants into the workpieces. The dopant ions modify the composition of t...

AI Technical Summary

Problems solved by technology

However, the use of a fixed threshold current limits the effectiveness of the arc protection circuit 30 because the threshold should be set high enough to avoid false triggering

However, due to different process recipes and operating conditions, the current supplied by the various power sources can vary enough that the fixed threshold current cannot detect some arcing conditions, if any, in a timely manner

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