METHOD FOR MEASURING THE BEST FOCUS USING LASER STEP ALIGNMENT SENSOR IN NIKON SCANNER

摘要

invention Nikon scanners using laser step alignment sensor optimal measurement method to focus on will. ; best focus measuring method using a laser step alignment sensor Nikon scanner of the present invention is a method for measuring the best focus pattern of equipment for the exposure process, (a) each of the source and the distance between the centers of the two won adjusting a diameter of; (B) wherein (a) forming an overlap of the elliptical shape in the test pattern through the stage; And (c) has a technical feature in yirueojim including the step of measuring the optimum focus value of the equipment by using the generated pattern. ; Thus, the laser step alignment sensors in the scanner of the present invention Nikon Using the best focus measurement method has the advantage of improving the best focus of the device on the minimum line width by making the shape of the pattern is two circles overlapping in order to improve the focus, the best pattern is effective to obtain a stable process margin.