公开(公告)号：US20190120617A1

公开(公告)日：2019-04-25

申请号：US16170085

申请日：2018-10-25

Applicant: Axcelis Technologies, Inc.

Inventor： John F. Baggett ,  Billy Thomas Benoit ,  Joe Ferrara ,  Brian Terry

IPC: G01B11/27

Abstract: A workpiece alignment system is provided has a light emission apparatus that directs a light beam at a plurality of wavelengths along a path at a shallow angle toward a first side of a workpiece plane at a peripheral region. A light receiver apparatus, receives the light beam on a second side opposite the first side. A rotation device selectively rotates a workpiece support. According controller determines a position of the workpiece based on an amount of the light beam received through the workpiece when the workpiece intersects the path. A sensitivity of the light receiver apparatus is controlled based on a transmissivity of the workpiece. A position of the workpiece is determined when the workpiece is rotated based on the rotational position, an amount of the light beam received, the transmissivity of the workpiece, detection of a workpiece edge, and the controlled sensitivity of the light receiver apparatus.

公开(公告)号：US10794694B2

公开(公告)日：2020-10-06

申请号：US16170085

申请日：2018-10-25

Applicant: Axcelis Technologies, Inc.

Inventor： John F. Baggett ,  Billy Thomas Benoit ,  Joe Ferrara ,  Brian Terry

IPC: G01N21/00 ,  G01B11/27 ,  H01L21/24 ,  H01L21/68 ,  H01L21/67

Abstract: A workpiece alignment system is provided has a light emission apparatus that directs a light beam at a plurality of wavelengths along a path at a shallow angle toward a first side of a workpiece plane at a peripheral region. A light receiver apparatus, receives the light beam on a second side opposite the first side. A rotation device selectively rotates a workpiece support. According controller determines a position of the workpiece based on an amount of the light beam received through the workpiece when the workpiece intersects the path. A sensitivity of the light receiver apparatus is controlled based on a transmissivity of the workpiece. A position of the workpiece is determined when the workpiece is rotated based on the rotational position, an amount of the light beam received, the transmissivity of the workpiece, detection of a workpiece edge, and the controlled sensitivity of the light receiver apparatus.