Pattern generator

• US 20100208327A1
• Filed: 04/28/2010
• Published: 08/19/2010
• Est. Priority Date: 03/02/1998
• Status: Active Grant

• Current Assignee: Torbjorn Sandstrom
• Original Assignee: Torbjorn Sandstrom
• Inventors: Sandstrom, Torbjorn
• Granted Patent: US 7,957,055 B2
• Time in Patent Office: Days
• US Class Current: 359/290
• CPC Class Codes: B23K 26/032 using optical means
• CPC Class Codes: B23K 26/064 by means of optical elements, e.g. lenses, mirrors or prisms
• CPC Class Codes: B23K 26/0648 comprising lenses
• CPC Class Codes: B41J 2/465 using masks, e.g. light-switching masks
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 27/0043 in projection exposure systems, e.g. microlithographic systems
• CPC Class Codes: G02B 27/4205 having a diffractive optical element [DOE] contributing to image formation, e.g. whereby modulation transfer function MTF or optical aberrations are relevant
• CPC Class Codes: G03F 7/2022 Multi-step exposure, e.g. hybrid; backside exposure; blanket exposure, e.g. for image reversal; edge exposure, e.g. for edge bead removal; corrective exposure
• CPC Class Codes: G03F 7/70041 by pulsed sources, e.g. multiplexing, pulse duration, interval control or intensity control
• CPC Class Codes: G03F 7/70283 Mask effects on the imaging process
• CPC Class Codes: G03F 7/70291 Addressable masks, e.g. spatial light modulators [SLMs], digital micro-mirror devices [DMDs] or liquid crystal display [LCD] patterning devices
• CPC Class Codes: G03F 7/704 Scanned exposure beam, e.g. raster-, rotary- and vector scanning mask projection exposure involving relative movement of patterned beam and workpiece during imaging G03F7/70358
• CPC Class Codes: G03F 7/70475 Stitching, i.e. connecting image fields to produce a device field, the field occupied by a device such as a memory chip, processor chip, CCD, flat panel display
• CPC Class Codes: G03F 7/70725 control
• CPC Class Codes: G09G 3/2007 Display of intermediate tones
• CPC Class Codes: G09G 3/346 based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833
• CPC Class Codes: H04N 1/195 the array comprising a two-dimensional array or a combination of two-dimensional arrays
• CPC Class Codes: H04N 2201/0414 Scanning an image in a series of overlapping zones
• CPC Class Codes: H04N 5/7458 the modulator being an array of deformable mirrors, e.g. digital micromirror device [DMD]

Abstract

The present invention relates to an apparatus for creating a pattern on a workpiece sensitive to radiation, such as a photomask a display panel or a microoptical device. The apparatus may include a source for emitting light flashes, a spatial modulator having modulating elements (pixels), adapted to being illuminated by the radiation, and a projection system creating an image of the modulator on the workpiece. It may further include an electronic data processing and delivery system receiving a digital description of the pattern to be written, converting the pattern to modulator signals, and feeding the signals to the modulator. An electronic control system may be provided to control a trigger signal to compensate for flash-to-flash time jitter in the light source.

Claims

1. An apparatus for a system including an optical system for projecting an image of a spatial light modulator (SLM) onto a workpiece that is positioned on a moving stage, the workpiece being printed with radiation modulated using the SLM, the apparatus comprising:

a continuous laser source configured to emit a continuous laser; and

an electro-optic scanner configured to scan the continuous laser over the SLM such that the SLM is uniformly illuminated.

2. The apparatus of claim 1, wherein said SLM is a matrix of pixels with only a few lines of pixel elements in at least one direction.

3. The apparatus of claim 1, wherein the continuous laser and the electro-optic scanner together are configured to achieve a controlled scanning rate over the SLM.

4. The apparatus of claim 1, wherein the continuous laser is a continuous ultra-violet (UV) laser.

5. The apparatus of claim 1, further comprising:

an optical system configured to project an image of the SLM onto the workpiece positioned on the moving stage to expose the workpiece.