Up-To-Date Activities Of Pxl (Proximity X-Ray Lithography)

PXL technologies in Japan have highly improved during the period of ABET program. A newly developed EB writer and the writing processes achieved accuracy of image-placement < 10 am and CD uniformity < 7nm (3 sigma). Together with the improvement of absorber materials, X-ray masks required for the 100 am technical node were fabricated and those for 70 nm node are within achievable levels. The alignment accuracy about 20 am and the use of magnification correction have verified the overlay accuracy < 30 nm, which is sufficient to 100 nm node. By improving the alignment accuracy, the exposure of 70 am node may be possible by using the present stepper. Furthermore, the next generation system with shorter wavelength may open the door for 50 am node and below.