Bois Columbes, France, December 4, 2002. Marc Stehle, president of SOPRA S.A. and Yoshio Hinoh, president of Sumitomo Heavy Industry, Ltd. (Tokyo, Japan) have signed a license agreement for the manufacturing and sales of Excimer Laser Annealing Systems based on SOPRA VEL laser technology. The license makes the High-Pulse-Energy Excimer Laser technology available for Low Temperature Poly-Silicon (LTPS) mass production required in the manufacturing TFT (Thin Film Transistor) of future generations of Active Matrix Liquid Crystal Displays (AMLCD) and Organic Light Emitting Displays (OLED).
SOPRA S.A. is known for its lines of advanced thin-film metrology tools that are widely used in the semiconductor industry and Flat Panel Display industries. SOPRA has supplied excimer lasers since 1979. In the framework of EU205 Eureka European program, SOPRA was the first to demonstrate a 1 kW Excimer Laser source in 1992. Contrary to conventional approaches, SOPRA choose an original way, producing high energy per pulse (10 J) at reduced repetition rate (100 Hz). Thanks to this fundamental choice, SOPRA is now the only commercial supplier in the world able to design and manufacture high energy Excimer Laser systems.
In the mid 90's, SOPRA developed for a Japanese customer an industrial VEL15 laser for TFT annealing process. The X-ray pre-ionized discharge pumped XeCl laser delivers 15 J in a 170 ns long pulse at 308 nm wavelength. A 62 J energy per pulse Laser was also developed in 1996 by using an amplifier chain based on the VEL15 technology.
Commercialized in 1997, the VEL15 laser is capable to process full size display without any of the very annoying overlap problems, or a very long scanning line with a wide and sharp plateau which also considerably reduces overlap non-uniformity. In addition, its 170 ns long pulse duration leads to much larger poly-silicon grains than with other more conventional short pulse systems.
Recently launched, new SOPRA VEL1510 laser with a pulse-to-pulse stability of better than 1.5% is now the most stable high power Excimer Laser. Its 15 J energy (up to a maximum of 23 J) and repetition rate of 10 Hz enable the same panel production throughput as with other existing scanning type annealing systems, while the high laser stability ensures a higher process yield. The Cost of Ownership of SOPRA VEL1510 laser is drastically improved in comparison to high-repetition rate laser systems due to significant cost reduction in annual maintenance and services.
Sumitomo Heavy Industry (SHI) has been supplying for several years laser annealing systems based on XMR technology. The acquisition of the outstanding SOPRA VEL1510 laser technology brings SHI to the forefront of Low Temperature Poly-Silicon Flat Panel Display Industry.
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