Shallow angle, multi-wavelength, multi-receiver, adjustable sensitivity aligner sensor for semiconductor manufacturing equipment
US10794694B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 2018 |
| Grant date | Oct 6, 2020 |
| Priority date | — |
| Expiry date | Dec 15, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/682
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.