Laser Optics for a Laser Line of 100mm Length using Pulsed Solid State UV Lasers
VOLCANO® Line Beam systems is designed for a line lengths up to 100mm. The use of solid state lasers emitting UV light at 343nm reduces the operating costs and increases the uptime of production tools remarkably, compared to ELA systems using excimer lasers.
The LB systems are based on a rigid aluminum housing structure and the FALCON XL projection lens gives a working distance of >200mm. A stable and solid system structure is needed to support the line beam optics. Line Beam Optics include a MBC (Manual Beam Control) camera system which allows to control and adjust position and angle of all laser emitted beams. The FALCON XL design contains one or two windows which seals the optics from the process chamber and protects against contaminations from the process.
The energy density up to 500mJ/cm² is obtained by using 4 TruMicro 7370 (20mJ specification) with 100mm x 100µm FWHM line beam.
VOLCANO LB 100UVC-4 configuration
The new VOLCANO LB 100UVC-SLA Laser Optics was developed for UV Solid State Laser Annealing (SLA). INNOVAVENT could demonstrate in the application lab, that regular grain structures are obtained in a 50-70nm a-Si film with the 343nm pulsed Line Beam. The regular grain structure is mandatory in the manufacturing of Thin Film Transistors (TFT) for high resolution AMOLED displays.
SLA SEMs of a VOLCANO 100UVC processed a-Si film showing a regular grain structure
with a period about equal to the wavelength 343nm of the laser light (left overview, right detail)
The VOLCANO LB 100UVC includes the following module options:
• Short Axis Flat Top (SAFT) optics
• Gaussian Short Axis (GSA) optics
• Polarization setting (in scan direction or in direction of the long axis or mixing long axis and scan direction)
• Pulse Delay and Temporal Profile control
• µ-Smoothing module (dynamic shift of long axis while scanning)
• PISTAB (Peak Intensity Stabilization) module („real time“ compensation of slow laser power variation)View into the line beam housingMoving process chamber and substrate chuckView on two TruMicro 7370 lasers, showing also the beam coupling modulesSAFT high power beam profile measurementThe INNOVAVENT application lab offers 5-50mm/s (0,5-5µm pitch at 10 kHz laser repetition rate) scan speed setting. Further the moving processing chamber provides N2 purging to create an O2 concentration lower than 20ppm at the substrate exposure area.
|Technical Data: VOLCANO® LB 100UVC-4|
30 up to 100µm FWHM (Gaussian profile)
40 - 50µm FW 95% (Flat Top)
<=3% (p2p ~ 6Sigma)
up to 500mJ/cm² @ 100µm FWHM or 50µm FW 95% (Flat Top)
15-20ns, can be extended by delay trigger scheme
2 - 4x TruMicro 7370 (Trumpf Lasertechnik)
|Diagnostics:||laser power meter, substrate power meter, substrate beam profiler, fast photodiode|
|Other line sizes and other configurations on request.|
VOLCANO® Laser Optics include an integrated attenuator module to adjust the energy density at the substrate level. Power meter heads and a CCD camera based beam profile measurement tool are available.