Optical lithographic device having a machine frame with force compensation
US5172160A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1991 |
| Grant date | Dec 15, 1992 |
| Priority date | — |
| Expiry date | Oct 29, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/709
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical lithographic device having a machine frame (1) to which is fastened a lens system (11) having a vertical optical main axis (13). Below the lens system (11), a positioning device (35) is fastened on a support member (3) of the machine frame (1), by means of which device an object table (27) is displaceable relative to the lens system (11) over a guide surface (5) of the support member (3) extending perpendicular to the optical main axis (13). The device is provided with a force actuator system (67) fastened to a reference frame (83) and controlled by a feedforward control system (95). The force actuator system (67) exerts a compensatory force on the support member (3) with a direction opposite to a direction of a reaction force simultaneously exerted by the positioning device (35) on the support member (3), and with a value which is substantially equal to a value of the said reaction force. The control system (95) further comprises a negative acceleration feedback (107), whereby the force actuator system (67) exerts a control force on the support member (3) which is determined by an acceleration of the support member (3) measured by an acceleration transducer (111, 113, 1…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.