Pre-alignment measurement device and method
US10197390B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2015 |
| Grant date | Feb 5, 2019 |
| Priority date | — |
| Expiry date | Dec 30, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7088
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A pre-alignment measurement device includes, disposed in a direction of propagation of light, a laser, a first cylindrical lens, a first imaging lens, an illumination diaphragm, a second imaging lens, a second cylindrical lens and a CCD detector. The laser, an object under measurement and the CCD detector are arranged at respective apexes of a triangle formed by the measurement device for pre-alignment. A light beam is emanated by the laser and is transformed into a line beam. The line beam is reflected by the object under measurement and then passes through the second cylindrical lens to form a CCD image which has different horizontal and vertical magnifications, allowing horizontal and vertical resolutions to be matched with horizontal and vertical measuring ranges, respectively. The CCD image contains information of a position and a height of a step defined by the object under measurement and the wafer stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.