Conventional approaches to photolithography are usually based on exposing through a chromium-glass mask manufactured by specialist vendors. In R&D environments it is often necessary to change the mask design frequently. Direct-write lithography tools (also known as digital mask aligners or maskless aligners) overcome this problem by holding the mask in software. Rather than projecting light through a physical mask, direct-write lithography uses computer-controlled optics to project the exposure pattern directly onto the photoresist.
MicroWriter ML3 Pro is our flagship machine within the MicroWriter ML family and is a compact, high-performance, direct-write optical lithography machine which is designed to offer unprecedented value for money in a small laboratory footprint. Sitting on its own vibration-isolation optical table, its only service requirement is a standard power socket. A temperature-compensated light-excluding enclosure with safety interlock allows it to be used equally well in an open laboratory environment or in a clean room. Easy to use Windows® based software means most exposures can be set up and launched with just a few mouse clicks. Four different minimum feature sizes (0.6µm, 1µm, 2µm and 5µm) can be selected automatically via software. This allows non-critical parts of the exposure to be performed rapidly while retaining high resolution writing for critical parts. An additional 0.4µm minimum feature size is available as an option. The MicroWriter ML®3 Pro features an optical surface profilometer tool and an automated wafer inspection tool for examining fabricated structures. A backside alignment camera for aligning double-polished wafers is available as an option.
• 195mm x 195mm maximum writing area.
295mm x 295mm maximum writing area available as an option.
• 230mm x 230mm x 15mm maximum wafer size.
330mm x 330mm x 15mm (customisable up to 330mm x 330mm x 175mm) maximum wafer size available as an option.
• 0.6µm, 1µm, 2µm and 5µm minimum feature sizes across full writing area. 0.4um minimum feature size available as an option.
• Automatic selection of minimum feature size via software – no manual changing of lens required.
• 385nm long-life semiconductor light source, suitable for broadband, g-, h- and i-line positive and negative photoresists (e.g. S1800, ECI-3000, MiR 701, SU-8). Replacement 365nm lightsource available as option for improved performance with SU-8 photoresist. Dual wavelength option (405nm lightsource and 365nm lightsource, software selectable) available for best performance across g-, h-, and i-line photoresists.
• XY interferometer with 1nm resolution for precise motion control.
• Extremely fast writing speed – up to: 15mm2/minute (0.6µm minimum feature size), 50mm2/minute (1µm minimum feature size), 120mm2/minute (2µm minimum feature size) and 180mm2/minute (5µm minimum feature size). These allow a typical 50mm x 50mm area combining critical and non-critical areas to be exposed in under 30 minutes or a typical 100mm x 100mm area to be exposed at 2µm minimum feature size in under 2 hours.
• Autofocus system using yellow light with real-time surface tracking laser– no minimum wafer size.
• High quality infinite conjugate optical microscope with x3 aspheric objective lens, x5 and x10 Olympus plan achromatic objective lens, x20 Olympus plan apochromat objective lens, and yellow light illumination for alignment to lithographic markers on the wafer (±0.5µm 3σ alignment accuracy). x50 Olympus plan apochromatic objective lens available as an option.
• Automatic changing between microscope magnifications via software – no manual changing of lens required. Additional x4 digital zoom can be selected in software.
• Grey scale exposure mode for 3-dimensional patterning (up to 768 grey levels).
• Software API for external interfacing and control.
• 30nm minimum addressable grid. 12.5nm minimum addressable grid available as an option. 4nm sample stage resolution.
• Acceptable file formats: CIF, GDS2, BMP, TIFF, JPEG, PNG, GIF; Oasis, DXF, Gerber RS-274X acceptable via Clewin 6 conversion.
• Automatic laser-based wafer centring tool.
• Built-in 2-dimensional optical surface profiler (100nm thickness resolution) for examining exposed resists, deposited layers, etching and other MEMS process steps.
• Automatic wafer inspection tool allowing each die on a wafer to be imaged.
• Virtual mask aligner mode in which the pattern to be exposed is displayed on top of the real-time microscope image, allowing the machine to be used like a traditional mask aligner.
• Autocalibration tool allowing users to check and correct calibration.
• 2D barcodes can be automatically generated through software for exposures. The software can then identify the developed barcode patterns and reads the contents.
• Emailing multiple users when exposures are finished.
• Multiple wafer / chip handling, allowing different exposure patterns and alignment coordinates to be supplied for multiple wafers or chips on the chuck. Used for exposing multiple users’ samples overnight.
• Includes passive vibration-isolation optical table.
• Light-excluding enclosure with safety interlock and temperature compensation to ±0.25⁰C
• Easy to use, Windows® based control software supplied.
• Supplied with Clewin 6 mask design software.
• Supplied with pre-configured 64-bit Windows® 10/11 PC with monitor, keyboard and mouse.
• Includes on-site installation by trained service technician.
• Extremely competitively priced for University and industrial R&D budgets.
• 90-260 VAC, 50-60Hz, 4A single phase power requirement.
• Footprint 90cm (w) x 75cm (d); height 153cm (including optical table; excluding PC workstation).
• CE-marked and compliant with EN-61010.